Short of piggybacking on a friend's site, you need to find a
webhost where you register a domain of your choosing and upload your index.html. These days they have web pages you can visit that allow you to upload that way, or ask them for instructions on how to FTP (file transfer protocol) to the web server using
Fetch on a Mac. This is a simple GUI program for uploading web files to/from your computer to a web server. Of course you could use FTP in terminal mode on a mac but Fetch is great for novices and pros with an easy to use interface.
Here's a great link with help and listings of popular inexpensive web hosts.
It could be as simple as
godaddy.com at $4.99/month, but there are plenty of topics on here about recommended webhosts and you should not forget to use Google to search for more webhosts and compare yourself. But this reply and others like it on here should get you started.
If you are looking for a
FREE webhost - my advice is to stay away from those entirely, they will either spam you, insert adware or banners, offer little to no support and generally run slowly with excessively high down time compared to others. Some of these don't require domain registration, but using their domain to save money isn't personal and like I said above, plenty of low cost solutions for both domain registration and webhost.
-jim