Can not edit content/images in Categories

I’ve been attempting to edit some of the content and images that I’ve got in categories. The problem is when I go to edit the page, instead of seeing the traditional layout with most pages: Visual and Text area to add content etc. it’s gone and all I’m left with is the Yoast section and the category details section. Unfortunately I can’t edit the images I’ve already got there or alter/add any of the content on the page. What am I doing wrong? And what should I do in order to edit and fix the content of those category pages?