Trouble with Sub-categories

I'm having some trouble with adding in subcategories to the Characters section marked on the navigation bar ( there seem to be two different Characters pages: one is just a regular page and the other is a category page ). What I was trying to accomplish was to have it so when you click the Characters tab on the navigation bar, you would see the words 'category page' on the upper left of that article, followed by the words 'pages in Category "Characters". Then below THAT, it would have the sub-categories: Males, Females and Animatronics ( the animatronics page MIGHT be messed up as well. idk ). The other category, the category page, can be found in the 'categories' category. For some odd reason, whenever I try to add categories to the characters like: Males, Females, Those Nights at Rachel's, etc, it seems to put all of the characters in the category page instead of the page on the navigation bar. I also can't seem to delete the Characters category page. If this is confusing to understand, may someone reply back. If someone could help me this problem, that would be awesome; I've been trying to fix the problem for a couple of days now and to no avail.