This all may sound hard and difficult but its rather easy once you know how it works.

Just follow me along on this journey to write a basic multiplayer game!

We will write a server that will be a seperate .NET core application which is also using C# , and we will use the same UDP library as for Unity.

The server runs independently from any Unity programs.

Our client will be written in Unity and C# and will contain the player stuff.

Both will be using the same library "LiteNetLib" which is a very competent library for UDP (and also Reliable UDP)

At the end we will have a way to send and receive data and we will be able to join the server with our game clients and see each client on the game and move around and see the movements.