"create a new folder called currency inside the player with a string value called souls and save when player leaves game."

-- server script 
local DataStoreService = game:GetService("DataStoreService")
local currencyDataStore = DataStoreService:GetDataStore("CurrencyData")

game.Players.PlayerAdded:Connect(function(player)
    local currencyFolder = Instance.new("Folder")
    currencyFolder.Name = "Currency"
    currencyFolder.Parent = player
    
    local souls = Instance.new("StringValue")
    souls.Name = "Souls"
    souls.Parent = currencyFolder
    
    local savedData
    local success, err = pcall(function()
        savedData = currencyDataStore:GetAsync(player.UserId .. "-Souls")
    end)
    
    if success and savedData then
        souls.Value = savedData
    else
        souls.Value = 0
    end
end)

game.Players.PlayerRemoving:Connect(function(player)
    local currencyFolder = player:FindFirstChild("Currency")
    if currencyFolder then
        local souls = currencyFolder:FindFirstChild("Souls")
        if souls then
            local success, err = pcall(function()
                currencyDataStore:SetAsync(player.UserId .. "-Souls", souls.Value)
            end)
            
            if not success then
                warn("Failed to save data for " .. player.Name)
            end
        end
    end
end)