When a user sends a request, it first reaches public/index.php, which starts Laravel. Then bootstrap/app.php loads the application. The HTTP Kernel receives the request and runs the middleware. After that, Laravel matches the request to a route, which calls the appropriate controller. The controller interacts with the model, the model accesses the database, and finally the controller returns a view or JSON response to the user.

1. public/index.php

require __DIR__.'/../vendor/autoload.php';
$app = require_once __DIR__.'/../bootstrap/app.php';

• Loads Composer's autoloader.
•  Loads all installed packages.
•  Creates the Laravel application.

2. bootstrap/app.php

This file creates the Laravel application.

$app = new Illuminate\Foundation\Application(
    $_ENV['APP_BASE_PATH']
);

• retrive instance of application
• Loads configuration.
• Initializes the Service Container.
• Register kernal

3. HTTP Kernal:

app/Http/Kernel.php 

• Receives the request. 
• Runs global middleware.
•  Passes the request to the router.

4. Router:

User request router decides which controller should execute.

5. Controller:

6. Model

7. View