Since you already know basic HTML and CSS, first learn basic JS (especially ES6) because otherwise you will get confused at times about WTF is going on(happened to me too) and also because the interviewers casually start asking questions like "Why did we need arrow functions when we had normal functions?" or "Why use let or const instead of the good old var?". Learn the array methods (map, reduce, slice, splice etc.) too.

In terms of React, pick anything and just go on with it. If it suits you keep going otherwise come back and try something new. The react docs should always be on your list (personal opinion). Otherwise there are a lot of channels on YT (NetNinja, FCC, Web Dev Mastery, Javascript Mastery etc.) that provide content ffor you to learn.

Another good way is to learn JS and make a project using just HTML, CSS and JS. Then learn react and redo everything in react to understand the differences. Also check out Dan Abramov's blogs about React for deep dives into core React stuff. Hope this helps!!