You may want to review our documentation
https://fusionauth.io/docs/v1/tech/connectors/
In contrast to using an OIDC Identity Provider, with a Connector the user doesn’t choose their identity provider; the administrator does. In addition, if the data source contains additional user profile information, a Connector allows you to map that into your user object. Finally, the data provider doesn’t have to implement the OIDC specification.
Let us know if you have additional questions!
Thanks,
Josh