How to enter the application through Yandex OAuth and work with the logged in user in loopback js?

Question

JavaScript

There is an application that consists of a client part written in react and a server part written using loopback JS. You need to configure user authentication through Yandex OAuth authorization, but all user roles and their rights to access data are registered in the loopback.
Yandex OAuth is needed to use Yandex disk in the application.
How to enter the application through Yandex OAuth, and at the same time add it to the database using loopback? It turns out that Yandex will have its own token, and its own for loopback. Can one be replaced by another?
Where to shove the authorization logic? Create a separate server that you can access when you need to log in? And how to authorize (check the rights) of the user while the program is running?