How do I add fire to a player in a script?

I am making a gamepass and I need to know how to add fire to the player after they have purchased it. I need to add the fire after the last if isPurchased then.

Also tell me what I need to add to make it work smoothly.

local passId = 932281642 --change this to your GamePass Id
local marketplaceService = game:GetService("MarketplaceService")
 
marketplaceService.PromptPurchaseFinished:connect(function(player,assetId,isPurchased)
	if isPurchased then --if the player did pay
		if assetId == passId then --if what they bought is the pass
			print(player.Name .. " bought the pass (" .. passId .. ")")
			if isPurchased then
				
			end
		end
	end
end)

But then someone said to do this... and it didn't work.

local passId = 932281642 --change this to your GamePass Id
local marketplaceService = game:GetService("MarketplaceService")
 
marketplaceService.PromptPurchaseFinished:connect(function(player,assetId,isPurchased)
	if isPurchased then --if the player did pay
		if assetId == passId then --if what they bought is the pass
			print(player.Name .. " bought the pass (" .. passId .. ")")
			if isPurchased then
			local fireMe = Instance.new("Fire",player.Character.Torso)
			
		end
	end
end)

Well if you have a player value,

local f= Instance.new("Fire",player.Character.Torso)