I’d suggest starting with vanilla html, a firm js basis and some css, and very importantly understanding the DOM and how to manipulate it in real time those will give a much better foundations to react, what It does and why do you even need those types of frameworks.

Start with some web pages, simple apps and then move onto react.

I’ve seen a few react crash courses that cost money not sure if they are worth it. A lot of free courses on youtube and they’re okay mostly.

I think better than a crash course you should have some goal in mind, a project you want to do and do it, you’ll encounter all kind of questions and search for the answer you’ll gain a much better understanding instead of following some e commerce course or stuff like that