How do I make a gamepass thats doubles the strength you earn?

I am making a simulator game that gives strength everytime you click the screen with the tool in your hand

I am confused on how to make the gamepass that doubles the strength you gain from the tool

Notes - The remote is "Swing" and the leaderstats value is "Strength" and the tool that fires the remote is "Knife"

Scripts

Script that gives strength -

local replicatedStorage = game:GetService("ReplicatedStorage")
local remoteData = game:GetService("ServerStorage"):WaitForChild("RemoteData")

local cooldown = 0.5

replicatedStorage.Remotes.Swing.OnServerEvent:Connect(function(player)

	if not remoteData:FindFirstChild(player.Name) then return "NoFolder" end

	local debounce = remoteData[player.Name].Debounce

	if not debounce.Value then
		
		print("got past the debounce if statement")

		debounce.Value = true

		player.leaderstats.Strength.Value = player.leaderstats.Strength.Value +15

		wait(cooldown)

		debounce.Value = false
			
	end

end)

I suggest searching on the internet on how to make this before actually asking it. There are guides on how to make it, but regardless, here you go.

We can use a service called MarketPlaceService. It's basically a service that is responsible for all the game monetization.

So first, create a gamepass under your game's name. If you created it, get the Service by calling game:GetService()

local MPS = game:GetService("MarketPlaceService")

So now we got the Service, we can get the Player's userId by using player.UserId in your script. Now let's perform a check if the player has the game pass.

(Make sure you already got the game pass ID, it can be found on the URL of the game pass)

local MPS = game:GetService("MarketPlaceService")

replicatedStorage.Remotes.Swing.OnServerEvent:Connect(function(player)
	local ownGP
	pcall(function() -- I'm not sure if you need this, this is just how I was taught..
		ownGP = MPS:UserOwnsGamePassAsync(player.UserId,  4) -- replace 4 with your game pass ID
	end)
end)

Now we just checked if the player has the game pass. You can perform the checks on the Clients if you want; don't get scared, Exploiters can't access MarketPlaceService.

Now, we just do the usual thing, sanity checks and all that.

local MPS = game:GetService("MarketPlaceService")

replicatedStorage.Remotes.Swing.OnServerEvent:Connect(function(player)
	local ownGP
	pcall(function() -- I'm not sure if you need this, this is just how I was taught..
		ownGP = MPS:UserOwnsGamePassAsync(player.UserId,  4) -- replace 4 with your game pass ID
	end)

	if ownGP then -- If player has gamepass
		player.leaderstats.Strength.Value += (15*2)
	elseif not ownGP then -- If player doesn't have gamepass
		player.leaderstats.Strength.Value += 15
	end	
end)