The Templates page is located in the left side-bar on your project dashboard.

 

International data privacy laws require that saved templates are only available for use in the data center region where your project is hosted (check the Datasite security and governance FAQs for additional information).

If the template you are attempting to save is not available in your selection list, it's likely you're attempting to save a template across data center regional jurisdictions. Select the data location in the upper right to switch regions.