Update Variables on Prefabs in a List?

I am working on a Turn Based Combat System.

The concept in my head is this:

Player selects the Level, then selects their Characters and hits play. Play will send the selected character IDs to the server and their selected level ID. The server will send back their selected character IDs with updated stats and their appearance IDs that get applied to prefabs in the level. Now once these prefabs are created in the "world". I would like to have a gameobject that will call "Turn Manager" to be able to update these prefabs all at once every turn.

Each unit has a Speed and a Turn Meter. Every turn their meter will go up by a certain percentage and once they have full turn meter they will get to take their turn. I have all the math and script concepts done but I'm not sure how I can make the "Turn Manager" actually update every single Character Prefab's turn meter all at once every turn.

Is their a way I can add each prefab to some form of list and then have the "Turn Manager" Call each of their current Turn Meters to see who is next and tell each prefab to call a function like IncreaseTurnMeter() that will handle increasing their Turn Meter?