Well all I'll say is; there's no need to give up yet!

If you want to start modding, I personally think it's best to start by focussing on one aspect of the game. For me that was the campaign map.

If you can try your hand first at editing existing regions, then adding new regions, then moving/adding generals and buildings, then eventually you can make a new campaign map.

This is what got me going with modding, the rest came later, when I had a better idea of what was and was not possible.

I can refer you to my guide on campaign map editing; I wrote it for RTW, but as M2TW is an evolution of RTW I believe all of what I wrote still applies.

However, I think Alpaca adapted my guide for M2 somewhere, I'll get you a link if you like, that would be better.