How does networking work?

i was looking on youtube for tutorials how to create a dedicated server game.
There are none, none which just show how to connect a player to a server.

How do i setup everything? I know a thing called “Switch Has Authority”, so far i know there must be “Server Files” and “Client” to run a MMORPG for example.
Server Files are uploaded to a FreeBSD Server and Client is downloaded by users/players.
How does it work on Unreal Engine 4? All i know about networking is that you can select if a blueprint or a function should run on Client or on Server by using “Switch Has Authority”.
But how do i setup “functions” for server? Do i need to create a “GameInstance” and use there “Switch Has Authority” for Server to make run things like “Health” “Damage” “Mana” etc?
Or do i set this up in the “FirstPersonBP” and use “Switch Has Authority” to server?

Switch has authority has 0.0% to do with a server “running” anything, it is a simple macro that checks if the exe is coming from a server or not, seriously just double click that node macro and look inside it. All its for is preventing clients from running something they shouldn’t, not “it makes the server run something”.

Here is a little something I put together a while back that might help get you started…

Unreal Engine 4 - (Tutorial) Quick And Dirty Blueprint Shooter Replication

If you like what you learn in this video, feel free to join my patreon page, where a lot more indepth tutorials live!