I know there’s been a lot on here about the topic, but none of it that i found is really helpful.
Basically i would probably like to start simply with being able to play my game with someone else in my house (On a different computer). I would then try to expand on that by having multiple servers and playing with random people like other games.
UE4 use more professional term called “Replication”, as network multiplayer is about replication of one state in another state in different computer. So if you search by “replication” you might find documentation and tutorials ;] Here overall documentation about online multiplayer:
UE4 Networking is working through a listen host. This listen host has all rights for replication, which means, that every time a client wants to display or share something, he needs to ask the sever for this.
This is handled by replicated variables and actors that are shared across the network and replicated function that are executed on servers but called from clients and other way round.
I made a basic Networking Stream a few weeks ago, maybe this helps you:
There is also a Framework Page for the Network that tells you which class works for what and which classes are available on clients and server and which not: