I've recorded a few footage sequences on my Canon 5d mkIV with the dimensions being 4096 × 2160. Once or twice I've created a clip in Premiere Pro, but the finished result never looks to be of a good quality, so I guess I'm either missing something when I import and/or export.

I really want to set up Premiere Pro correctly from the start, but the stock sites all seem to have different requirements - I've had a couple of clips accepted on Shutterstock, but when I try and upload to Dreamstime I'm told they are the incorrect format. I exported as Quicktime, but I think I actually ended up with clips that only had dimensions of 1920 x 1080, and if I try to overwrite this before export, the larger parameters are not accepted.

Does anyone have a link or set of instructions that can make this a little more simple for a beginner?

Swich to LUMIX GH5 and won't have any issues! Cheaper but much,much better quality than 5d mkIV