users:

countries:

app/Models/User.php

                namespace App\Models;
  
                use Illuminate\Contracts\Auth\MustVerifyEmail;
                use Illuminate\Database\Eloquent\Factories\HasFactory;
                use Illuminate\Foundation\Auth\User as Authenticatable;
                use Illuminate\Notifications\Notifiable;
                use Laravel\Sanctum\HasApiTokens;
                
                class User extends Authenticatable
                {
                    use HasApiTokens, HasFactory, Notifiable;
                
                    /**
                    * The attributes that are mass assignable.
                    *
                    * @var  string[]
                    */
                    protected $fillable = [
                        'name',
                        'email',
                        'password',
                    ]; 
                
                    /**
                    * The attributes that should be hidden for serialization.
                    *
                    * @var  array
                    */
                    protected $hidden = [
                        'password',
                        'remember_token',
                    ];
                
                    /**
                    * The attributes that should be cast.
                    *
                    * @var  array
                    */
                    protected $casts = [
                        'email_verified_at' => 'datetime',
                    ];
                
                    /**
                    * Get the comments for the blog post.
                    */
                    public function country()
                    {
                        return $this->belongsTo(Country::class);
                    }
                }

                

app/Models/Country.php

                namespace App\Models;
  
                use Illuminate\Database\Eloquent\Factories\HasFactory;
                use Illuminate\Database\Eloquent\Model;
                    
                class Country extends Model
                {
                    use HasFactory;
                }

                

using whereRelation()

                namespace App\Http\Controllers;
  
  use Illuminate\Http\Request;
  use App\Models\User;
    
  class DemoController extends Controller
  {
      /**
       * Write code on Method
       *
       * @return  response()
       */
      public function index()
      {
          $name = 'india';
          $users = User::with('country')
                          ->whereRelation('country', 'name', 'like', '%'.$name.'%')
                          ->get()
                          ->toArray();
    
          dd($users);
      }
  }

Output

Array

(

    [0] => Array

        (

            [id] => 1

            [name] => Hardik Savani

            [country_id] => 2

            [email] => savanihd@gmail.com

            [email_verified_at] => 

            [two_factor_secret] => 

            [two_factor_recovery_codes] => 

            [current_team_id] => 

            [profile_photo_path] => 

            [created_at] => 2020-09-12T06:46:08.000000Z

            [updated_at] => 2020-09-18T12:04:09.000000Z

            [deleted_at] => 

            [country] => Array

                (

                    [id] => 2

                    [name] => india

                    [code] => 2

                    [created_at] => 2021-08-09T14:58:47.000000Z

                    [updated_at] => 2021-08-09T14:58:47.000000Z

                )

        )

)

                

Using whereHas()

                public function index()
{
    $name = 'india';
    $users = User::with('country')
                    ->whereHas('country', function (Builder $query) use($name){
                        $query->where('name', 'like', '%'.$name.'%');
                    })
                    ->get()
                    ->toArray();
  
    dd($users);
}