To hide a page, you want to go to the pages section on the right-hand side.
Here you'll see there are some pages with this icon:
which means the page is hidden.
To get another page to be hidden, you just need to click on the three dots, click hide page, and you'll see the icon appear. This will also appear in the page bar along the top
To un-hide the page and show the page again, click the show page button here and the page will be visible in the live mode.