How do you make it so when the player stops moving they die?

basically as the title explains, When a player stops moving for more than a second they die, is there anyway to make that?

Here

if Humanoid.MoveToDirection.Magnitude == 0 then
	--kill
end

Insert in a local script and place in the player.

local player = game.Players.LocalPlayer

while wait(1) do
	if player.Character.HumanoidRootPart.Velocity.Magnitude < 1 then
		wait(1)
		if player.Character.HumanoidRootPart.Velocity.Magnitude < 1 then
			player.Character.Humanoid.Health = 0
		end
	end
end

You can use the Running event in the humanoid.

game.Players.PlayerAdded:connect(function(player)
	player.CharacterAdded:connect(function(character)
		local humanoid = character:WaitForChild("Humanoid")
		humanoid.Running:connect(function(speed)
			if speed > 0 then 
				print("player is walking")
			else
				character:BreakJoints() --same thing as Humanoid.Health = 0
			end
		end)
	end)
end)