How to get related tables?

Question

Laravel

There is a project in which there are 3 tables in the database, users, a list of sites and a table containing a list of sites associated with users. How to get a list of sites from the user model?
//tables: users, sites, site_user

Answer 1

User::find($userId)->sites();
But the links in the models must be spelled out

Answer 2

https://laravel.com/docs/5.7/eloquent-relationship...