How to make a key trigger while somebody is sitting on a vehicle seat?

So far I've only been able to do this with local scripts and not with regular ones. I want to make a forcefield-like wall inside of my vehicle that can be enabled and disabled with a certain key. LocalPlayer doesn't seem to exist inside of regular scripts. Is there a way around this?

Seats have a Property called Occupant you can check if it changed and see if its not nil then you would want to clone a local script to the players Gui now you need to assign a special name or just store it in a variable but i just store it in a name like the generateUUID function of HttpsService

local Seat = Script.Parent
Seat:GetPropertyChangedSignal("Occupant"):Connect(function()
	local Hum = Seat.Occupant
	if Hum then
		RandomName = game:GetService("HttpService"):GenerateGUID()
		local Player = Players:GetPlayerFromCharacter(Hum.Parent)
		local C = script.LocalScript:Clone()
		C.Parent = Player
		C.Boat.Value = Seat.Parent
		C.Name = RandomName
	end
	if Hum == nil then
		Players:FindFirstChild(tostring(RandomName),true):Destroy()
	end
end)

local seat = script.Parent
seat:GetPropertyChangedSignal("Occupant"):Connect(function()
	local hum = seat.Occupant
	if hum then
		local player = game.Players:GetPlayerFromCharacter(hum.Parent)
		local name = player.Name
		local p = game.Players:WaitForChild(name)
		local dee = game.Players.."."..name
		local mouse = dee:GetMouse()
		mouse.KeyDown:Connect(function(key)
			if key == "F" then
				local b = Instance.new("Part")
				b.Parent = workspace
			end
		end)
	end
end)

This is what I have right now It's telling me "Attempt concatenate Instance with string"