attempt to index nil with 'KeyDown' ?

Hello, i have this script that spawns a trap, but it dosent spawn in? Can someone help?

local plr = script.Parent.Parent.Parent.Parent
local mouse = plr:GetMouse()

mouse.KeyDown:connect(function(Key)
	local k = Key:lower()
	if k == "CTRL" then
		if k == true then
			local trap = game.ServerStorage.Trap:Clone()
			trap.Parent = workspace
			trap.Position = plr.Character.LeftFoot
			plr.Character.Humanoid.Jump = true
		end
	end
end)

Thanks!

Roblox does not recommend using mouse.KeyDown as it is deprecated. Use UserInputService instead. Make sure it is a localscript.

local plr = script.Parent.Parent.Parent.Parent --So many parents
local UIS = game:GetService("UserInputService")

UIS.InputBegan:Connect(function(input, GPE) --Input is self-explanatory, GPE stands for Game Processed Event.
	if GPE then return end --If the player is e.g. chatting, then do nothing.
	if input.KeyCode == Enum.KeyCode.LeftControl then
		local trap  = game.ReplicatedStorage.Trap:Clone() --Serverstorage can only be accessed by server scripts.
		trap.Parent = workspace
		trap.Position = plr.Character.LeftFoot
		plr.Character.Humanoid.Jump = true
	end
end)

If it doesn't work, then you should use remote events instead. Edit: bruh I posted an answer, and I also used comments to explain stuff.