Step 1: download & install nodejs package

Go to nodejs

Step2: check version

                            node -v
                            npm -v
                        

Step 3: Start Build Your Project

                        npm init
                        

STEP 4: install express js

                        npm install express
                        

Step 5: create server.js file

                        const express = require("express");

                        var app = express();

                        app.listen(5000, function () {

                            console.log("Started application on port %d", 5000);

                        });

                        

Step 6: run

                        node server.js
                        

Step 7 : npm start

in package.json

                        {
                        "name": "node_app",
                        "version": "1.0.0",
                        "description": "1",
                        "main": "index.js",
                        "scripts": {
                            "test": "echo \"Error: no test specified\" && exit 1",
                            "start" : "node server.js"
                        },
                        "author": "",
                        "license": "ISC",
                        "dependencies": {
                            "express": "^4.18.1"
                        }
                        }

                        

run

                            npm start 
                    

Step 8: send response to web

                    const express = require('express');

                    const app = express();
                    const PORT = 3000;

                    app.get('/', (req, res)=>{
                        res.status(200);
                        res.send("Welcome to root URL of Server");
                    });

                    app.listen(PORT, (error) =>{
                        if(!error)
                            console.log("Server is Successfully Running, and App is listening on port "+ PORT)
                        else
                            console.log("Error occurred, server can't start", error);
                        }
                    );