Looking for Document Tool

I’m looking for a plug-in that will allow me to upload files to site and they appear automatically on one of my pages based upon how I categorize it or something like that. I’ve installed WP Download Manager and for some reason, they really do a good job hiding instructions for how to use it. I’ve searched and searched and find nothing so I’m about to give up on it. I’m just looking for some simple way I can control files I’m hosting and then easily add to my pages.