Hi @kevin15,
Welcome to Auth0 Community!
At the moment, Enterprise connections can only be shown as buttons if you are using Organizations, as Identifier First + Home realm Discovery is not yet supported in Organizations. We do however have plans to include support for it hopefully early next year. Here is some additional information regarding these upcoming changes: Support/Replace Organization prompt screen with "choose organization" during login - #17 by adam.housman
Thanks,
Dave