Use the managed domains feature. From the docs:
Adding one or more managed domains for this configuration will cause this provider not to be displayed as a button on your login page. Instead of a button the login form will first ask the user for their email address. If the user’s email address matches one of the configured domains the user will then be redirected to this login provider to complete authentication. If the user’s email address does not match one of the configured domains, the user will be prompted for a password and they will be authenticated using FusionAuth.