In order to add a Menu page type you need to access your application's dashboard and go to "Edit pages" section. Click on Add New Page button, the "+" button below the list of the currently available pages.
Once added you may go to Edit the page.
Here, you may add as many menu items as you need, just make sure that all of those have other pages linked to each of the item from the list.
In the "Menu Items" section, you may click on "+" button to add more menu items.
Below you may find the Items Proprieties section. Here, you may change the title/label, image/thumbnail and the Link-To page of the item selected in "Menu Items" section.