Not OP, but I used Namecheap. Porkbun is also recommended I think. Setting it up is not dead-brain simple, but Proton does a very good job on explaining it step by step I believe.

I use Porkbun for my domain. you can get a .xyz domain for only $2 for 1 year, though after 1 year its like $8 per year.

I’m using namesilo and it was pretty straight forward to set up. I just got it a couple days ago and no issues so far!

IIRC Cloudflare is the only registrar that doesn’t mark up from wholesale prices, or something like that. Basically makes them cheaper than most other registrars. I think the point is that they can then sell you their other (related) services more easily — the services that actually make them money.