@”Kapítan Denis” I did that with Morrowind, in fact that’s how I first got interested in coding and modding in general. Morrowind comes with TES Construction Set, similar to Skyrim’s creation kit. First I just downloaded mods for the game like you described, but then I started opening everything in that construction set. I’d go through bunch of scripts in the game and later other peoples’ modes. I was 12-13 at the time and was surprised how it’s all easy to understand and replicate. People are still making Morrowind mods, 16 years after it’s release. Now I have it with official DLCs and a graphic overhaul mod.
I never got into modding Skyrim because I wanted vanilla experience first time finishing the game. Besides that my computer is relatively weak for certain mods, I’d be watching blue screens and it shutting down due to overheating pretty frequently.