If you want to get yourself the;
Radeon 5700 XT -- $400~
Ryzen 5 3600 -- $150~
1TB SSD (Samsung) - $100~
Power supply at least 600 Watts - $50 - $100
Mother board just get anything that supports Ryzen 3rd series - $100 - $150
16 GB RAM DDR4 or you can get the minimum which is 8GB at least the standard. (Depending on which MHZ for the RAM) $80 - $160
One you're saving a bit money.. You could buy the Windows on other key selling ($25) uhhh and you would just have to build it.. get a Case, mouse, keyboard, monitor and you set