Personally, I became a better developer when I sought out a small local business that wanted a website built from the ground up. I charged them a modest amount for this website, and I had no prior knowledge of how to build it.
I built the website from scratch, using HTML, CSS and Angular 1.6.
I then bought a domain, and space on a server.
The whole experience of designing, building, implementing and deploying made me a very independent, skilled programmer.
Aside from that, there are many ways.
Hope this helps!