Content > Pages > Navigation

There are 3 columns setup to display the first level navigation in separate columns eg. (Column 1, Column 2, Column 3).  The names of these columns reside in the navigation tree first level and should not be changed.  You can add any number of children links as needed.

If a page is placed in the navigation tree the page URL will include parent links (/column-3/courses).  To remove the column-* part of the url you can go to the page,  select the edit pencil next the URL and update as needed.