You can hide your specific page from the navigation bar by toggling on or off the Show in navigation option. Note that this does not make the page invisible to visitors, as it only hides it from the Navigation Bar. If visitors have the URL of the page, they will be able to access it.
1. Select Content in the gray navigation bar.
2. Select the gear icon to the right of the Page title you would like to hide, and click on the toggle button that is next to Show in navigation. Blue means that it is active!