1 Create the Django project and app by using the below command

                    django-admin startproject core
                    cd core
                    python manage.py startapp authentication

                    

2. Register app name 'authentication' in Installed_Apps in settings.py file.

                    INSTALLED_APPS = [
                        "django.contrib.admin",
                        "django.contrib.auth",
                        "django.contrib.contenttypes",
                        "django.contrib.sessions",
                        "django.contrib.messages",
                        "django.contrib.staticfiles",
                        "authentication", // App name 
                    ]

                    

3. in authentication/view.py

# Import necessary modules and models
from django.shortcuts import render, redirect
from django.contrib import messages
from django.contrib.auth import authenticate, login
from django.contrib.auth.decorators import login_required
from django.contrib.auth.models import User
from .models import *

# Define a view function for the home page
def home(request):
    return render(request, 'home.html')

# Define a view function for the login page
def login_page(request):
    # Check if the HTTP request method is POST (form submission)
    if request.method == "POST":
        username = request.POST.get('username')
        password = request.POST.get('password')
        
        # Check if a user with the provided username exists
        if not User.objects.filter(username=username).exists():
            # Display an error message if the username does not exist
            messages.error(request, 'Invalid Username')
            return redirect('/login/')
        
        # Authenticate the user with the provided username and password
        user = authenticate(username=username, password=password)
        
        if user is None:
            # Display an error message if authentication fails (invalid password)
            messages.error(request, "Invalid Password")
            return redirect('/login/')
        else:
            # Log in the user and redirect to the home page upon successful login
            login(request, user)
            return redirect('/home/')
    
    # Render the login page template (GET request)
    return render(request, 'login.html')

# Define a view function for the registration page
def register_page(request):
    # Check if the HTTP request method is POST (form submission)
    if request.method == 'POST':
        first_name = request.POST.get('first_name')
        last_name = request.POST.get('last_name')
        username = request.POST.get('username')
        password = request.POST.get('password')
        
        # Check if a user with the provided username already exists
        user = User.objects.filter(username=username)
        
        if user.exists():
            # Display an information message if the username is taken
            messages.info(request, "Username already taken!")
            return redirect('/register/')
        
        # Create a new User object with the provided information
        user = User.objects.create_user(
            first_name=first_name,
            last_name=last_name,
            username=username
        )
        
        # Set the user's password and save the user object
        user.set_password(password)
        user.save()
        
        # Display an information message indicating successful account creation
        messages.info(request, "Account created Successfully!")
        return redirect('/register/')
    
    # Render the registration page template (GET request)
    return render(request, 'register.html')


        

4. in authentication/models.py

        from django.db import models
        from django.contrib.auth.models import User

        

5. update database configuration in setting.py

6. migrate models

        python manage.py makemigrations
        python manage.py migrate 
        

7. create the super user by using below write command

        python manage.py createsuperuser 
        

8. url

        # Import necessary modules
      from django.contrib import admin  # Django admin module
      from django.urls import path       # URL routing
      from authentication.views import *  # Import views from the authentication app
      from django.conf import settings   # Application settings
      from django.contrib.staticfiles.urls import staticfiles_urlpatterns  # Static files serving

      # Define URL patterns
      urlpatterns = [
          path('home/', home, name="recipes"),      # Home page
          path("admin/", admin.site.urls),          # Admin interface
          path('login/', login_page, name='login_page'),    # Login page
          path('register/', register_page, name='register'),  # Registration page
      ]

   

      

9. authentication/templates/login.html

      <!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Login</title>
    <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>
    <div class="container mt-5">
        <!-- Login form -->
        <form class="col-6 mx-auto card p-3 shadow-lg" method="post" enctype="multipart/form-data">
            <h1 style="text-align: center;"><span style="color: green;">GeeksforGeeks</span></h1>

            {% csrf_token %}  <!-- CSRF token for security -->

            <!-- Login heading -->
            <h3>Login</h3>
            <hr>

            <!-- Display error/success messages -->
            {% if messages %}
            <div class="alert alert-primary" role="alert">
                {% for message in messages %}
                {{ message }}
                {% endfor %}
            </div>
            {% endif %}

            <!-- Username input field -->
            <div class="form-group">
                <label for="exampleInputEmail1">Username</label>
                <input type="text" class="form-control" name="username" id="exampleInputEmail1" aria-describedby="emailHelp"
                    placeholder="Enter username" required>
            </div>

            <!-- Password input field -->
            <div class="form-group">
                <label for="exampleInputPassword1">Password</label>
                <input type="password" name="password" class="form-control" id="exampleInputPassword1" placeholder="Password" required>
            </div>

            <!-- Link to registration page -->
            <p>Don't have an account <a href="/register/">Register</a> </p>

            <!-- Submit button -->
            <button type="submit" class="btn btn-primary">Submit</button>
        </form>
    </div>
</body>
</html>

      

10. authentication/templates/register.html

      <!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" rel="stylesheet">
    <title>Registration Form</title>
</head>
<body>
    <div class="container mt-5">
        <!-- Registration form -->
        <form class="col-6 mx-auto card p-3 shadow-lg" method="post" enctype="multipart/form-data">
            {% csrf_token %}  <!-- CSRF token for security -->

            <!-- Registration form heading -->
            <h1 style="text-align: center;"><span style="color: green;">GeeksforGeeks</span></h1>
            <h3>Register</h3>
            <hr>

            <!-- Display error/success messages -->
            {% if messages %}
            <div class="alert alert-primary" role="alert">
                {% for message in messages %}
                { { message }}
                {% endfor %}
            </div>
            {% endif %}

            <!-- First Name input field -->
            <div class="form-group">
                <label for="exampleInputEmail1">First name</label>
                <input type="text" class="form-control" id="exampleInputEmail1" aria-describedby="emailHelp"
                    placeholder="Enter First name" name="first_name" required>
            </div>

            <!-- Last Name input field -->
            <div class="form-group">
                <label for="exampleInputEmail1">Last name</label>
                <input type="text" name="last_name" class="form-control" id="exampleInputEmail1"
                    aria-describedby="emailHelp" placeholder="Enter Last name" required>
            </div>

            <!-- Username input field -->
            <div class="form-group">
                <label for="exampleInputEmail1">Username</label>
                <input type="text" class="form-control" name="username" id="exampleInputEmail1"
                    aria-describedby="emailHelp" placeholder="Enter email" required>
            </div>

            <!-- Password input field -->
            <div class="form-group">
                <label for="exampleInputPassword1">Password</label>
                <input type="password" class="form-control" name="password" id="exampleInputPassword1"
                    placeholder="Password" required>
            </div>

            <!-- Link to login page for users who already have an account -->
            <p>Already have an account <a href="/login/">Login</a> </p>

            <!-- Submit button -->
            <button type="submit" class="btn btn-primary">Submit</button>
        </form>
    </div>
</body>
</html>

      

11. authentication/templates/home.html

      <!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title style="color: green;">Welcome to Geeksforgeeks ????</title>
    <style>
        .container {
            text-align: center;
            margin: 100px auto;
            max-width: 500px;
            padding: 20px;
            background-color: #fff;
            border-radius: 10px;
            box-shadow: 0 0 10px rgba(0, 0, 0, 0.2);
        }

        h1 {
            color: green;
            font-weight: bold;
        }

        img {
            width: 60%;
        }
    </style>
</head>
<body>
    <div class="container">
        <!-- Page heading -->
        <h1>Welcome to Geeksforgeeks ????</h1>
        
        <!-- Animated GIF -->
        <!-- Use "welcome.gif" as the source for the GIF -->
        <img src="https://i.ibb.co/RNB6jpM/welcome.gif" alt="Welcome Cartoon">
    </div>
</body>
</html>

      

12. run

      python manage.py runserver