Agree with kztcaliber
I learned from the same way, W3schools but I also learned from Documentation, StackOverflow, and various Neocities websites (which also has their own HTML tutorial!). I have my own physical server for running a Jellyfin and Minecraft server for friends with a Reverse Proxy VPS to tunnel traffic to it.
I can’t quite say it would be wise to use a Old PC running Linux to run a website (although many websites are running some kind of Linux). Especially when it comes to security. You have to remember that it will potentially expose your IP address...
Just rent from a host unless you are experienced in security, all the security is usually built in whereas you’d have to manually do it yourself, living with constant fear of being DDOS’d, lawl.