I really wouldn’t get too hung up on how React works at first. I would suggest you take a more practical approach in the beginning. Then later it can be good to dive deeper into how things work. You can create pretty solid and well functional apps without knowing much about the internals of the framework.
It is for the same reason I never really agreed with tutorials that showed React.createElement when first teaching JSX. I don’t think it’s bad to know how JSX actually works but I do think it’s a distraction when first starting out.
I’m just saying this because I don’t think the reason you do not understand React all that well yet is because of the lack of answers to the questions you posted in your first post. I think you can learn React and use it fairly well without knowing the answers to pretty much any of the questions you posed.
Again, I’m not saying it isn’t good to want to understand things more deeply and I can empathize with feeling a disconnect between the tools and what they do and how they do it. But learning a tool and knowing how a tool works isn’t necessarily as closely related as you might think. Just like you can learn to tell time without knowing how a clock works.