How to create the right JS application architecture?

Question

Node.js

I create a chat with a friend. He does the front, I do the back. Back on express, front on pure js (and this and that on typescript). I want to learn how to create architecture correctly, namely:

• What folder structure should be?
  
• What and how to collect webpack? (one of the reasons for creating a project is to figure it out) Is it needed for the back or just for the front? If needed, in what cases
  
• In plans to use sockets. Is this the right choice? If so, what are the "good practices" in dealing with them?
  
• How to "dock" front and back? So far, 1 page has been made, which is spit out by express via sendFile (is this generally correct?). But what if more pages are needed? How to store information between pages? I thought about local storage and cookies, would it work? What other options are there? What's the best way to organize it all? How to move from page to page? Regular links?
  
• How to properly commit? We are currently using this strategy .
  

I will be glad to any advice. Just links or at least the names of resources where you can read / watch are enough.
It would also be interesting to look at the "correct" repositories to see what interesting solutions others have