These tutorials use Unity v2021.1, and MLAPI 0.1.0 . For imformation on modyfing the code for use with Netcode for GameObjects please see here
This Unity Multiplayer tutorial will teach you how to create your own lobby where players can join and ready up before starting a match.
Video published 22nd Jul 2021
For project files access, check out the repository here: https://github.com/DapperDino/Unity-Multiplayer-Tutorials
For more information on Serialization see About Serialization in the main MLAPI documentation.
Thank you to DapperDino for the video tutorials! These contributions are a fantastic help to the community.