Going back through your specs…bro a 4090 costs basically the same as my whole PC that’s running games at 120 FPS+ on a 4k monitor with no issues.
Check out combo deals on Newegg for Mobo+RAM+CPU, or Microcenter if you have one nearby (I don’t). Your biggest factor for gaming will be the GPU. You can run 60+ FPS on a 1080P monitor on 5 year old midrange GPUs. If you need 4k res, ask on PCPartPicker forums.
It’s unfortunately a valid “defeatist” point that I hate finding myself falling back into over and over on so many issues. It shouldn’t be so hard to say ‘yo can you stop taking advantage of me for personal financial gain in every possible scenario’?