Need help upgrading my PC to run games at max settings and 60-70 fps (The Witcher GTA Fallout, Star Citizen and BF1 in the future)

I want to make my PC my main platform for games, running games at max or high setting at 1920x1080 60fps, and a good monitor for games

My hardware price knowledge is very basic, so I'm gonna overprice a bit and say I have around 900$ to spend (Not counting the monitor)

I'm overpricing a bit since I live in Brazil, and the parts usually are more expensive

My current PC Build

My knowledge of hardware price is very basic, if the budget is too low feel free to exceed it.