XF 1.5 Node question

I am making a buy and sell forum,

are there any options to link category? becasue its to many forums if i want have 2 categories, i am having 15-16 forums in 2 categories and its to much on the front page.

the site node is not what i want because its just making a list of the forums
It was not what i was looking for.

I will try to explain.

This is just an exampel.

I have 2 categories side by side (using a UIX theme)

when i push one category it flips open and show all my forums under it. But the other category is still by its side.
I was wondering if there is a setting to change so when i push one category it flips open in a new window or does some other thing, so the other category doesnt show and take up space on the site.

uploaded files to see

. onecategory.PNG tocategories.PNG tocategoriesopen.PNG