Record Types
The Record Types section decides which Records can use this template. Turn the switch ON next to each Record Type the template applies to.
When a template is associated with a Record Type, it appears in the dropdown next to the New Portal button on the Portals panel of every Record of that type, so internal users can create a portal from it with one click. A template with no Record Types cannot be started from a Record, but it can still be used by the Create Portal Package workflow action, which lists every template.
Only Record Types that have Users will be able to create and share collaboration portals turned ON in the Record Type editor can host portals at all. Associating a template with a Record Type that has that switch OFF has no effect until the switch is turned on.