Please refer below link for Linux Ip Networking
https://www.cs.unh.edu/cnrg/people/gherrin/linux-net.html#tth_chAp1
Please refer below link for Client-server framework for a multiplayer game
http://www.lucadavidian.com/2020/10/25/client-server-framework-for-a-multiplayer-game-part-1/
Basic Socket Skeleton