Basically laravel is a backend programming language framework and its PHP so definately laravel most important thing is to build API's.
And the another side we have react which is the latest framework of javascript which is made up of Facebook for front end side.
So React developer + laravel developer = Full Stack developer
so basically you have two sides web or App
you build API's for the help of controllers and that controllers gives the response in
JSON's format when the App developer call the controllers
your controllers are attached your module and your your module are connected to your
database.
you write a code of javascript inside of Json's