Guest can be done in multiple ways. The template: "Guest Access" will create a RADIUS service that is used by Aruba controllers or Instant to authenticated clients.
The "Guest Access - Web login" template creates an Application authentication service that is used internally by the ClearPass guest page to do authentication.
Then there is a third template: "Guest Authentication with MAC Caching", which creates two RADIUS services, one for MAC authentication and a second RADIUS similar to the first template.
If this explanation is not clear, you may check Aruba Solution Exchange for an even more sophisticated wizard. The in-product wizard should be considered starting point, and most times require an understanding of ClearPass to tailor it to your exact needs.