What is your budget? There’s not a lot of difference, some have better warranties than others, some have different coolers, it comes down to preference. EVGA is well known, Asus makes decent stuff, I’ve used Zotac over the years as well. Some folks don’t like gigabyte but I’ve used a lot of their motherboards and those are usually fine. I currently have an MSI card, but it is an amd rx 6700xt, and it’s good so far.
As far as nvidia, they have good products. AMD has a lot of good products as well. They’ve come a long ways. I would argue that around the 300 dollar range the rx 6600 is probably a better buy the the nvidia rtx 3050 since it’s closer to the rtx 3060 if you aren’t worried about ray tracing.