Ruby on Rails API behind Keycloak for beginner?

I am investigating Keycloak for authn/authz use for a new Ruby on Rails app. Since I have little experience with auth*, I am looking for more specific guides that illustration integrating Keycloak with Rails. Are there any good guides for this combination of tools?

There are a couple of Rails Gems, and I am currently looking at https://github.com/looorent/keycloak-admin-ruby ; however, it doesn’t go into detail on how to setup basic auth.

For comparison, the Keycloak docs illustrate how to use Keycloak in front of an app - in this case, keycloak.org/app. I don’t know what’s going on behind the scenes in the Keycloak demo app. The Keycloak demo app has a Sign In button, and that sends me to my local keycloak server’s Log In form. There I can login with Github (which I connected to keycloak), and eventually I get sent back to the keycloak demo app.

This is the basic functionality I am trying to replicate with Keycloak + Rails: to illustrate using Keycloak in front of Rails.

Suggestions, direction, and links to guides are welcome.

Thanks in advance!