You can assign pages to groups using Page Group Tags and then assign a menu to that group.
In the example below we have added the tag 'portfolio' to all the pages that we want to display or work.
To assign a menu to a Page Group:
1. Add a Menu page from the Add menu on the left tool bar.
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2. Make sure the new menu is selected and then change the Menu Target field to the Page Group that you want, in this case 'Portfolio'.
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