Quick netoworking overview in C++

Can someone briefly explain me how a network system is setup using C++ (I only found documentation and tutorials for blueprint scripting on the web).

For example, how do I create/join a LAN session using c++?

The best resource for this is shootergame (on the learn tab I believe), it has multiplayer C++ working examples. I would start there and then come back and ask specific questions once you’ve read through the code.