When you first set up a site by adding a Drive Folder or Team Drive, Overdrive will make a page for each folder within the chosen Site Folder. Each page will have a Page Type of Google Drive Folder - since we don't know what you want your site to be yet.
So, when you first visit your site it will look like Drive with each page showing the contents of it's Drive Folder. If most of your pages will remain as Google Drive Folder types you can set their default properties on this tab. You can then change any individual pages in Page Settings.