Well, first, understand that all those games you mention above cost many millions of dollars to develop, with teams of 100 or so people working for several years. That’s roughly equivalent to one person working for several hundred years, assuming the same skill level as the pros who made those games.
So that just means you will need to adjust your expectations accordingly.
I haven’t used any of those assets, so I can’t comment on how well they can do what you want. However, most assets include source code, so you would be able to adjust them and build on them when you have built the skill to do so.
One of the other forum members put together this Getting Started FAQ , which I think would be a good place for you to begin.
Good luck!