Use of EXPERIMENTAL - User role mapping

How do I use the experimental role mapping feature?

I have the following roles in Drupal: Administrator, Center Administrator, Editor, Publisher.

In the "experimental user role mapping" section, these roles are displayed with text boxes next to them, but I'm unsure what to write in these boxes.

I also don't know which claim I need to retrieve from my external provider, whether it must be called "groups," or if a custom claim is allowed.

Furthermore, I've created a user field called "groups" so that it shows up in the OpenID Connect settings, allowing me to select my provider's claim from a dropdown. However, I'm not sure if this field serves any purpose for role mapping.

Thank you very much!