[HELP] How do you change variable from server to client?

Like the title says how would I go about setting a variable from the serverside and have it change clientside.
I’m trying to change an amount from my 3D2D which is obviously clientside but I need it to change when something happens in serverside.
the variable is waterlevel

[editline]14th November 2016[/editline]

Also another question so I don’t have to make a new thread.
How do I make it so when a entity is on TOP of another entity I can detect that?
So like if I had a pot on a stove.

You want to use net messages. Broadcast your variable from the server to the clients, each time it changes.

okay thats what I though I didn’t know it didn’t update automatically so thats why I thought it wasn’t working thx I guess i’ll just have it send everytime its updated