spotify-web-api-php | A PHP wrapper for Spotify 's Web API | REST library

(Where abouts should I save this file?)

You can save this file in differents places in laravel, for testing you could write it in a controller (not the best but you can).

Do replace client id and secret with my detail?

Yes of course !

also how do I save the access token?

You can save in a database or in a session or where you want. If you store it in a session you will have to make a new request to get a new Access token if the user logged out of your application. In a database you can reuse it.

Many access token are only available for a specific duration. The spotify doc should speak of it.

(Where do i also save this file and how do I make these calls in my Laravel Controllers?)

For testing you can do this in your controller, but it's a good idea to have a service layer where you put the business logic of your application.

Do not copy require 'vendor/autoload.php'; in your file laravel handle the composer autoload already.