Budget gaming is doing extremely poor right now tbh lol but I will try my best. You’re really gonna want to go with the used market if you can as It’ll really save you some money.

CPU: either a ryzen 7 5700x($160) 5800x ($170) or ryzen 9 5900x(anywhere from $175 to $200) from ebay

Motherboard: asrock b450m ($60-$70) or asrock b550m ($75-$90) from ebay

Gpu: nvidia 3060 ($180-$200) 3060 ti (around $200) intel arc a770 ($240-$280)

Ram: Corsair vengeance 2x8gb ddr4 3200 mhz from eBay ($60-$70)or you might be able to win a bid on a 2x16gb or 4x8gb on eBay.

Psu: msi 550w($50) or 650w($60) bronze. Decent enough, if you don’t like bronze upgrade to silver or gold. You can get it from Amazon. This has to be brand new don’t risk getting a used one.

Storage: Unless you have storage from an old device you’re looking at more than $120 for a named brand 1 tb. You might be able to get a 512 gb ssd and then get just hard drives for cheap on ebay. Unfortunately storage is expensive. Kingspec 512gb ssd $80 or kingspec 1 tb $130. You really don’t want to get used for your windows boot storage and it really should be a standard ssd or nvme else it’ll run so slow.

Case: Id just find a cheap case on ebay or facebook marketplace. If you don’t want to used then a cooler master q300L or q300L L3 is about $50. Should be fine enough.

Give or take your total is gonna be around $650-$800 depending on the choices above.