To update your Laravel version from 5.7 to 8, you need to follow a series of steps. Here's a step-by-step guide:
1. Update Composer:
```
composer self-update
```
2. Update Laravel Installer:
```
composer global require laravel/installer
```
3. Create a new Laravel 8 project:
```
laravel new my-project
```
Note: Replace "my-project" with the desired name of your project.
4. Compare the default Laravel 8 project structure with your existing Laravel 5.7 project structure and make note of any differences.
5. Copy your application code from the Laravel 5.7 project to the Laravel 8 project, taking care to retain any custom modifications or packages you have installed.
6. Update your `composer.json` file in the Laravel 8 project to include any custom dependencies or packages that were present in your Laravel 5.7 project. You can compare the `composer.json` file of both projects to ensure you include all necessary dependencies.
7. Run composer update:
```
composer update
```
8. Check the Laravel Upgrade Guide for Laravel 5.7 to 8 and follow the guide for any specific changes you need to make to your codebase. You can find the upgrade guide at: https://laravel.com/docs/8.x/upgrade
9. Test your application thoroughly to ensure all functionality is working as expected.
10. Make any necessary adjustments to your code to address any deprecations or breaking changes introduced in Laravel 8.
11. Update your server configuration to point to the new Laravel 8 project directory.
12. Once you have tested and confirmed that your application is working correctly in the Laravel 8 project, you can safely remove the Laravel 5.7 project.
Remember to backup your Laravel 5.7 project before starting the upgrade process. This will allow you to revert back to the previous version in case any issues arise during the upgrade.
It's important to note that upgrading Laravel versions can introduce compatibility issues with your existing codebase, especially if there were significant changes between the versions. Therefore, it's advisable to thoroughly test your application after each step and address any issues that arise along the way.