Cloudflare, Google Domains, and Porkbun are all great choices (understandably, many users in this community will disregard one or both of the first two).
Some other recommendations: Which domain registrar should I pick? : webhosting
A lot of people recommend Namecheap. I strongly disagree with this recommendation. Firstly, Namecheap is not even that cheap — it’s more expensive than both Cloudflare and Porkbun. Namecheap is also notorious for scummy business practices such as, most notably, automatically renewing domains with auto-renew explicitly disabled.
If you are looking for anonymity/extreme privacy, the expensive OrangeWebsite is the only option I know of. OrangeWebsite accepts cryptocurrency and allows you to use their business information for your domain’s WHOIS records (note that you do not technically/legally own the domain if you do this). This is not the same as WHOIS privacy protection, which is a basic feature included for free with any decent registrar that prevents your personal info from being publicly accessible.
Linode (use Level1Techs’s affiliate link) has been my go-to VPS provider for years. They certainly don’t offer bottom-of-the-barrel prices, but their uptime and support has been absolutely rock-solid. I’m wary of Linode’s acquisition by Akamai, but so far I haven’t seen anything of concern.
DigitalOcean (use Lawrence Systems’s affiliate link) is another reputable provider that has been around for a long time. DO and Linode are pretty much direct competitors, so a lot of their pricing is matched to each other. However, I have less faith in DO nowadays after a public incident (OP / post-mortem by DO / later clarification by OP) and two data breaches (2020 / 2021).
Hetzner and Netcup seem to be frequently recommended on the basis of price, but you probably can’t expect the same level of polish and reliability as Linode and DO.
OrangeWebsite allows purchasing VPSes anonymously with cryptocurrency. These are very expensive though.
There are some other recommendations on Hacker News, notably to check LowEndBox and LowEndTalk if you’re in search of the cheapest VPS providers.