How to replace skybox, window glass, and Daedric Lord textures?

[EightPointStar]

Sorry if this has been answered elsewhere. I tried using the forum search first but couldn't narrow down the keywords enough to get any results. I'm also sorry if I don't refer to something correctly. This is the first time I've ever modded anything and I don't have all the terminology down yet.

I'm making my own loose file textures for now because I haven't wanted to learn Unity just yet. I've figured out a lot through trial and error, the Daggerfall Workshop Textures documentation, UESP, and random web searching. However, I haven't figured out how to replace certain things: the skybox, the glass in the windows, and the Daedric Lords. (I used console commands to summon one of them and the texture I created didn't show up.) Can I even do loose file replacements of these assets/textures?

Any help is appreciated!