I had a project built out in Projects but didn't realize I'd want to reuse it. I searched around for a hot minute looking for a way to turn it into a template. My feedback is that while this option exists, it is not simple and intuitive to find.
Support chat gave me this information to help: The details and steps of that are found here https://knowledge.hubspot.com/resources/how-to-use-the-hubspot-projects-tool
So it's hiding in here:
I'd suggest making "show product details" a button so it stands out, or perhaps renaming it to "project details and actions" to make it clear that it contains more than just the details. Alternatively, perhaps you could make these two options on the main screen: "project details" and "project actions".