How do I add another stat datastore save to my stats script?

Hello, So I'm making a game and I was wondering how can I add so my kills stat would save. I already added it so I just need the save thingy. The problem is that a guy on here gave me this script and I don't really understand it that much.

My code:

local DataStoreService = game:GetService("DataStoreService")
local CashDS = DataStoreService:GetDataStore("Cash")
local RS = game:GetService("RunService")

game.Players.PlayerAdded:Connect(function(plr)
	local Cash = Instance.new("IntValue")
	Cash.Name = "Cash"
	Cash.Parent = plr
	Cash.Value = 0
	
	local Kills = Instance.new("IntValue")
	Kills.Name = "Kills"
	Kills.Parent = plr
	Kills.Value = 0

	local data
	local g, err = pcall(function()
		data = CashDS:GetAsync("cash_"..plr.UserId)
	end)
	
	if not g then
		warn(err)
	else
		if data ~= nil then
			Cash.Value = data
		end
	end
end)

game:BindToClose(function()
	if RS:IsStudio() then return end
	local plrs = game.Players:GetPlayers()
	
	for _, plr in pairs(plrs) do
		local data = plr.Cash.Value
		
		if plr:FindFirstChild("TagValue") then
			data -= 50
		end
		
		if data then
			local g, err = pcall(function()
				CashDS:UpdateAsync("cash_"..plr.UserId, function(old)
					local new = old or 0
					new = data
					return new
				end)
			end)
			
			if not g then
				warn(err)
			end   
		end
	end
end)

game.Players.PlayerRemoving:Connect(function(plr)
	local data = plr.Cash.Value
	
	if plr:FindFirstChild("TagValue") then
		data -= 50
	end
	
	if data then
		local g, err = pcall(function()
			CashDS:UpdateAsync("cash_"..plr.UserId, function(old)
				local new = old or 0
				new = data
				return new
			end)
		end)
		
		if not g then
			warn(err)
		end   
	end
end)