This endpoint lets you get your corresponding template. If no template exists for the user, a template is created and sent back. You need to be subscribed to the Review Booster product.
The authentication system on Partoo API is using API Key that should be put in the header of the request (the name of the header is x-APIKey). An api_key is linked to a user. This user's role will give you different access level to the API features.