Your website can have a set of private pages which can only be seen when logged in. Creations and edition of these pages are done in the same way as public pages.
This is an example of a menu that is only shown to logged in users.
Create a page that appears in the navigation bar the same way you would a public page but ensure that the “Private page” box is ticked. Any pages created as sub-pages will also be private.
The above image shows the check boxes ticked to ensure a page is shown the the top navigation but only to when the visitor is logged in.
Simply create the page where you want it and select the “Private page” option.
Please note that if you link to a private page from a public page the page will still be accessible by visitors who are not signed in.