A quick video tutorial/example below. You should watch this in HD mode so you can see the details:
The steps are also listed below:
1. Go to the “Pages” section of the dashboard:
2. Click the “New page” button near the top of the screen:
3. Enter all of the details you would like in your page.
4. Don't forget to give your page a name/title at the top.
5. Click “Publish” to finish creating the page:
Ok, now your page is created! ...but why isn't it showing in the menu yet? Well, we still need to do that...
6. Go to the “Layout” section of the dashboard:
7. Click the Edit button in the “Pages” gadget, select the pages you would like to appear in the navbar and click “Save”:
You can also re-order the menu items by clicking and dragging them in the "List Order" section of this window.
Reblog https://support.pipdig.co/articles/blogger-how-to-add-pages-to-the-navbar-menu/