How do you make a overhead Gui that dects groups?

In my new game, Alfa Labs 2, I am trying to make a script that detects if you are in the Alfa Labs Group And says above your head, Group rank, And then shows pictures of the AL logo. How?

Do a server script inside ServerScriptService, and add this:

game.Players.PlayerAdded:Connect(function(plr)
	plr.CharacterAdded:Connect(function(char)
		if plr:IsInGroup(ID HERE) then
		--add the BillboardGui Here
		end
	end)
end)

Hope I helped.