How to Connect with own Usermodel

Hello i have in my Golang-App an Usermodel with many relations. It dosent make sense to make that as threats but i need a way to handle authentications(password,facebook, etc -> jwt-based if possible) and authorisations(handled over graphql (Client) and grpc(microservice other golang App)) How can i do that?

and how to use the Ory stack in an own Docker-Application. Cant find any Dokumentation about that. just the Docker aproach but i like to use it with my own App direct in Go use Ory Stack like Plugins.