I'm afraid this is something Flox is not very well suited for.
Flox doesn't allow for any real-time communication: you can store information on the server (via an Entity), but there is no notification mechanism that will tell other players that a value has changed.
So the other players would constantly need to load that Entity and check if it has changed. That is slow and expensive (it will use a high number of Flox-operations), and you'll probably run into synchronization issues (one player writes a value, another overwrites it just a few milliseconds later, so the counters will become wrong).
You will need to use a real multiplayer server for that game. This thread on StackOverflow lists some of the possible solutions.
Sorry that I don't have any better news!