There's some paradox with writing my own HTML. I my well go down that path, but as I'm learning, won't I be producing some junky code? And if my whole thing is to use it on my site... Well you get the idea.
That's the reason you use tools meant for it to help you, then clean the HTML if necessary. That gives you a framework for learning, and a safety net.
In particular, that https://html-online.com/editor/
link has a clean function built in, so you can paste code into it, and then clean it of any irrelevant tags that might be put in. There's also htmlkit that is a good, free editor for beginners. The latest version now costs money, but you can still download the free version at http://www.htmlkit.com/download/