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When you hide a page, it won’t show up in the menu, but people can still get to it with a link.
On a computer, open a site in new Google Sites.
At the right, click Pages.
On the page you want to hide, click More Hide from navigation.
To publish your changes, at the top right, click Publish.
You can’t hide the home page, but when you hide any other page:
Subpages are also hidden.
Other sites and pages can link to the page.