Hello, my amazing friend.
Both HTML and CSS can give a fundamental understanding of Web basics. I recommend skimming through HTML knowing the basic structure is good enough and spend more effort on CSS. Especially,
Flexof CSS, which will be used heavily in later project.
JS is a weird language, there are some of the main quirks you should get yourself familiar with. 1.
Object, 2.Function(normal & arrow function) 3.Difference between Class and function, 4.thiskeyword.
With some basic understanding of JS, Ts should be a small cake. But pay attention to
type union,type vs interface
Inside section, fundamentals of react is included covering JSX. This notes so far, only covers React, not React Native. However, the fundamentals are the same.