I built a website using plain HTML/CSS/JS; it could be anything as simple as a Tic Tac Toe game to something more feature rich. Most valuable lesson there was

I built a website using plain HTML/CSS/JS; it could be anything as simple as a Tic Tac Toe game to something more feature rich. Most valuable lesson there was in understanding what it's like to work with the native DOM, since that usually gets abstracted away when you throw in something like React/Angular/Vue. Then I rebuilt the same thing using Angular2+ and React, but paid attention to what set of things were made easier (and in some cases, more difficult). Once I got the basics down I picked one I liked (React) and began using it and diving more in-depth (best practices, reading blogs, codebases, etc.).