How to learn to write your React, Node js code?

Question

JavaScript

I've been learning JS for over a year now. At the very beginning, writing your code (out of your head) did not cause difficulties. But then there was a break in practice and now writing lightweight computational structures is not difficult.
But I want to write my own chat with authorization and I don’t even know how to approach it.
I can read ready-made code with almost complete understanding, but I can’t reproduce it myself, only copy-paste.

Answer 1

make a front page, write "hello test" or something on it.
Add a registration link to make it work.
add a login form and make it work.
then write a chat. ( _{**picture with an owl**} )

Answer 2

Watch videos, read articles. It is quite normal not to know how to implement something complex.
The knowledge and experience that we have now has been collected for decades. This is a natural process of evolution of any area, not just code.

Answer 3

websocket, side effects like redux-thunk or redux-saga, write your own simple state manager