It's incredibly easy.

When you look up google dot com, it takes you to a web site.

With #pubky you look up, not a domain name, but your public key aka your npub on nostr

And it takes you to your own website, that you choose and control.

Best of all this is secured by millions of nodes, so that there are no take downs, no gate keepers and censoring it requires taking down millions of nodes, but 100s more pop up in a second.