In Drupal, there are something call "primary and secondary links" on menus how would you add items to those menus links?
It is not too hard if you know what you are looking for!
The steps are very simple:
Click on "Administer" then click on "menus" then click on "primary links" and finally click on "add item".
On this screen, you would enter the information to show on your primary link menus.
Here is an example for adding Forum to your "primary links" menus:
Parent item: Primary Links
Here is some direct path if you want to know them:
› Site building › Menus > Primary links > Add item