Below is a screenshot of the page manager. This is the main area to organize your pages, change layouts associated with pages, delete pages, etc.
By default the Main Menu is the default menu for gpEasy. It has certain characteristics you need to be aware of.
Therefore, if you are using multiple additional menus in your gpEasy installation it might be a good idea NOT to use the Main Menu in a layout, and keep it available for organizational purposes--site map, galleries, etc.