Can I create private API Products?

You can definitely share an API product only to a selected number of profiles and keep the rest of your API products public.

When you create your API Product, you have two options: put it as public or private. When you put it as private, you make sure your API Product cannot be accessible from your public API Portal. Instead, you will need to invite some users to that product, by going to the Clients page and linking them to the private product of your choice.