Should I get unreal?

Hi, I am making an online comic using poser. I was wondering if I should get unity, at least for some backgrounds for my comic. Although my comic is free at present, one day it may be a commercial project. I read the EULA and it looks to me like movies and renders would belong to me and are royalty free. Did I read that correctly, or once my comic makes a fortune (ha ha) then do I have to pay the fee to UE? Will i be able to use the content that comes with unreal even for a commercial project eg an educational video? Is there a special commercial project licence that I should get? I have a high end mac.
What is the best version for me to download and how/where. I am totally new. Also i have no programming experience. I don’t want to do 3D modelling, but i do own a massive collection of 3d content i have purchased over the years eg renderosity and daz3d for use in poser. poser can export as .fbx also would i be able to import unity content into poser?
Kind regards,