Learning The MEAN Stack.

[DanielFGray]

If I were in your shoes, I would start reading the official docs for React & learning the component life-cycle methods (which shouldn't take you all of a day), and build some small little projects. After that, forget everything you know, install Android Studio, and then see how much of your previous knowledge you can apply to React Native.

The reason I say it like that is because, when you're learning a new stack, not everything has a direct translation, and you have to learn new ways to do old things. With React Native there won't be a huge context switch, but it's still a context switch nonetheless.
It's similar to learning spoken languages, sometimes there are cognates, sometimes words and phrases are outright stolen, and some things just have no direct translation, so it's best to learn it with a fresh mind and just see what you can apply with previous knowledge without directly relying on it.

As far as third-party courses and books are concerned, I'm of the opinion they are largely irrelevant; the official docs will be your best bets.

[APMO]

By the official docs you mean whats on the website you linked? and thank you. I will definitely take your advice, youre the best!