Once a site is created, multiple pages can be created for the site. These will not automatically appear on the site, they will need to be added to the "Navigation" in order for a page to appear on the site. The examples shown below are taken from the Snow and Ski Archive digital exhibit.
To add pages to the navigation so they will appear on your exhibit site, you'll need to add them from the right pane. Pages can be dragged for reordering and nested under other pages for subpages.