Problem with Categories

I hope this is the right place for it >.<....

Well, i know the difference between Caterogies and Forums.
My problem is that i somehow cant make Categories? Or i dont know how o.o
atm the only category on it is called "forum" which was there automaticly. When i try to add another Category it simply appears as forum in that Catergory? @_@
Could maybe someone explain me how to make new Categories and change the name of "forum" incase Im doing it wrong? >.<

You should read this
https://help.forumotion.com/frequently-asked-questions-f5/categories-and-forums-creation-and-appearance-t3313.htm