Ideas

I've been planning a PC build for my buddy and he doesn't know he's been using my old pre built PC which was an omen 30L 3700x/ 1660 super but now me and his mom are working on getting him a new one so far we have

Cpu- 5 7600x Mobo- Asus b650e white one (basic one) Psu- 850 cooler master modular Case- next h7 flow So far this is 304 dollars I'm trying to think of a GPU for him but idk what to get him since we trying to keep it under 600 ( Yes we have ssd , fans and stuff just junk stuff I have laying around just don't know what to do with GPU )