UE4 Multiplayer (UDP/TCP P2P)

Hi guys! I am a new game developer, and I started learning C++.
I want to make a dedicated server, but I don’t know what to do.
I think I may be able to program it, but I don’t know how it should work.
If I program simple dedicated server, do I need to make it based on unreal engien source code or not?
I want it to be lightweight.
If I make it without UE4, it is good idea to make it like this? :
First, download scene from server, load scene (on player side), and just simply get information where are the other players from server and then render them?

You might want to start here A new, community-hosted Unreal Engine Wiki - Announcements and Releases - Unreal Engine Forums

Writing your own server is almost certainly not what you want to do.