Navigation Overview
To edit the Navigation, go to Content > Pages > Navigation
Main Navigation in the Header
Creating your site's navigation is as simple as creating pages and quickly drag and dropping them to create your Site Map.
Child - 2nd Level
Child (2nd level) navigation items will display when the parent (1st level) is selected.
3rd Level
3rd Level navigation items will display when the child (2nd level) is selected.
This theme is not designed to show navigation items that are 4th level or beyond.
Resources
Video Tutorial: Adding A Navigation Item