So with the game I am trying to make the leaderboard invisible, and the hp bar at the top rigth go away. I forgot the exact code, could some one remind me please.
What you're looking for is the SetCoreGuiEnabled method of StarterGui.
In a LocalScript,
Game.StarterGui:SetCoreGuiEnabled(Enum.CoreGuiType.PlayerList, false)
To get this to run, though, you have to put the LocalScript where it will run, such as in the StarterGui