Org Resources pages, accessible in the side menu, are designed for three things:

  1. Provide private pages for non-admins to access that are not in the site navigation.
  2. Provide private pages that only admins can access.
  3. Supply content for use on frontend pages accessible to the general public.

The below articles show how to work with them.

Add/Edit an Org Resource page
Add an Org Resource Page to a Custom Web Page