I never took lessons to play the drums. I never took lessons to play the guitar. I just sort of figured it out. I think that if you’re passionate about something and you’re driven and you’re focused, you can do anything you want to do in life.
Pure functions (and thus React components) are much easier to test because they simply return a description for what UI of the component should look like, given some application state, rather than actually mutating the UI and having side-effects. This “description” is known as a “Virtual DOM” and is a tree-like data structure.