I have been working on learning how to implement multiplayer for unity projects using Mirror.
To use Mirror, you can click the link above and add it to your unity assets. Now go into your unity project and import Mirror using the package manager.
This will allow you to use the mirror features to host multiplayer servers.
In my prototype, players can join the game and be assigned a name and color. They are then able to move around. The server verifies all the players' changes and then sends them to the clients.