Holo help,I need this?

I am still working on a Holo and A LOT of people helped me,I want to thank them but I still need to finish the script. so heres what I got

a=Holo.config
b=a.RankId
c=a.GroupId
game.Players.PlayerAdded:connect(function(plr) 
if player:GetRankInGroup(c.Value) >= b.Value then 
player.Chatted:connect(function(msg)
	if string.lower(chat) == "sf" 
game.Lighting.Thing:Clone().Parent = game.Workspace
	elseif string.lower(chat) == "close sf" then
if game.Workspace:FindFirstChild("Thing") then
game.Workspace.Thing:Remove() 
end
	end