Adding a menu to top of 2016 theme

I am trying to create a menu on the very top of the 2016 theme.

I want it to be at the very top and left justified – and behave like the very top menu does on this page that uses a custom theme: https://midstateems.org/blog/

I am actually replacing the custom theme at https://midstateems.org/blog/ with the 2016 theme, but I want to add the same type of menu to the 2016 theme.

Suggestions appreciated. Many thanks