The navbar should be on the top of the course homepage. The link to the Course Admin should be added to the navbar by the site admin.
If you are not seeing the course admin in the list of the links in the navbar, I would suggest contacting your School Admin.
Additionally, depending on your user account permission, you may also be able to edit your own course navbar.
if you have permission, you should be able to follow this article and add the Course Admin to the navbar:
On the Edit Navbar page, you can do one or more of the following:
I hope this helps :)