Keycloak OpenID Connect Support

We are using “Zammad version 3.2.x” and there is a OAuth2 and SAML for third party authentication. Is it possible to connect with Keycloak OpenID with OAuth2? If there is any documentation to connect with Keycloak, Could anyone share it?

I followed the following link, and I could not find the files they mentioned to change for enabling OpenID connect.

$ sudo ls -al /opt/zammad/vendor/lib/oauth2_database.rb
ls: cannot access ‘/opt/zammad/vendor/lib/oauth2_database.rb’: No such file or directory
$ sudo ls /opt/zammad/vendor
assets bundle heroku pkgr plugins ruby-2.5.5