Hi mate,
You can find a brief documentation on the github .
https://github.com/jody-boelen/oauth
you can try visiting the repository. hope it helps!
great place to start is implementing this module and following the steps,
https://marketplace.mendix.com/link/component/117529
it depends if you only want to authenticate or do more and with which Identity Provider you want to connect but this module prob. will have you covered for the first steps