I would suggest a build with AM5 and X3D CPU. AM4 is a technical legacy and you can't upgrade to newer CPU generations with this socket.
Regarding RAM i suggest 32GB because 32GB is the current standard in gaming pc.
Regarding graphics i suggest a card with 16GB VRAM. A very good card with actual architecture is the RX 9070 XT. Or a RX 9060 XT if the first one is over your budget.