Visualizing and understanding all the bits and pieces 0 routers, bridges, subnets, addressing schemes.

However I think it would be alot easier to learn if put into game form.

Perhaps the game starts in a very simple network segment, like a home network.

Imagine packets flowing like water.

Your job is to get the water flowing from one point to another.

You need to put in place the right network devices - bridges/routers/whatever, and set the network settings properly to allow the water/packets to flow through to the next bit where you have to solve some new challenge.

I think even little kids could learn networking if it was in game form.

The guy who wrote "HackNet" has done a somewhar similar thing - made "real" technology into a game: https://www.pcgamer.com/hacknet-is-a-hacking-game-with-real-hacking/