Heya Mikey! Welcome to the forum!
I've taken a look at your website and I really like your art!
And as someone who became fascinated with computers and how they work at a very young age and even took a programming course in school I want to tell you that we never stop learning this things, there is always something more or something we missed, my favorite way of learning HTML/CSS is to look at the source of websites that have cool things, and modern web browsers make it super easy!
I'm also mostly a lurker but making an effort to be more social so I hope you have a nice time here!