Hi Phillip,
Azure AD B2C (Business-to-Consumer), supports a wide range of identity providers, not just Facebook and Google.
In the Azure portal, go to your Entra for Customers (Azure AD B2C) tenant > Identity Providers.
Also note that any application that supports SAML can use Entra for authentication.
References:
https://learn.microsoft.com/en-us/entra/external-id/
https://learn.microsoft.com/en-us/azure/active-directory-b2c/