How do I enable Azure AD sign-in directly on the Sign In page instead of having an additional page?

How do I enable Azure AD sign-in directly on the Sign In page instead of having an additional page?
You could promote AD B2C as the default identity provider.
"When an identity provider is set as the default, users who sign in to the website aren't redirected to the sign-in page. Instead, they sign in using the selected provider."
Have a look at this: https://learn.microsoft.com/en-us/power-pages/security/authentication/configure-site#set-a-default-identity-provider