On the tools bar of builder, Click “Insert Template”, you could insert some layouts including the placeholder templates. There are templates including Home Page, Single Projects, About/contact, Blog, and Sections. The “User” tab is for your own.
Click “Save Layouts as Template”, you could save the current layout as a new template. You would find the template in the “User” tab(Click “Insert Template” to find it). You could also save a Group layout to a new template.