If you require the navigation to show 2nd level menu, you need to make a very minor tweak to the master page that the site is using.
- Using SharePoint Designer (SPD), open the master page being used by the site. In SPD, navigate to _catalogs/masterpage/yourmasterpage.html
- In the master page file, search for SharePoint:AspMenu.
- You will more than likely have more than one instance of a menu control. Look at the IDs to find the right navigation control for what you want to edit. They are intelligently named, you will be able to sort out which one you need. For default.master, look for ID=”TopNavigationMenu”.
- In the properties for the tag, find MaximumDynamicDisplayLevels=”1″. Change the number from 1 to 2. (You need to level till you need navigation)
- Save the file and publish the master page (do this from SPD, Manage Content and Structure, or the Master Page Gallery).
- Refresh your browser. Now when you mouse over menu, you should see another level of navigation pop up.
- If you have more than 2nd level of navigation, you have to first add them separately in global navigation first. Once you save your changes, edit top navigation, drag 2nd level navigation under 1st level navigation.
- If you have more than 2 level navigation, you won't be able to drag 3rd level navigation in 2nd level. For that you need to create your custom master page and do that process.