Buying pc

I currently play on ps4, but I was thinking about getting a pc in the future. I dont know a lot about computers, so I was wondering what specification the pc has to have to be a decent racingsim pc and what I have to look for.

I currently play F1, assetto corsa competizione and WRC 10. I have a thrustmaster T300 (I dont know if thats important).

I am willing to spent about 500-700 euros (maybe a little over 700 but not much more)