Two free choices I'm aware of, for hosting at a URL that both future-proofs your choice of hosting provider and provides end-to-end encryption to site visitors, are the free CloudFlare plan in front of GitHub or S3 (or any other static hosting service), and the free hosting plan on Netlify.
CloudFront is very cheap, but it is not free. (For that matter, S3 itself is cheap but not free.) It's therefore a solution to “I'm employed in a developed nation and don't want to notice that I'm paying for hosting”, but not to “I have literally no money to spare for hosting because a year is less than coffee” or “I want my content to stay up without my having to remember to keep a valid credit card on file somewhere”.
 CloudFront ≠ CloudFlare. Nobody in this thread has been confused about this, but it tends to trip people up.
 I ran tech ops for a company whose site was, on launch day, around the 55th-most-popular site on the internet. I think our CloudFront bill was $300 for that day.