Can anyone help me to fix a script intended to give player points via chat?

I know its very disorganized and extremely old for starters. I found this old script i tried editing it myself in order to make it work but I'm not sure what's wrong with it, if I could please receive so helpful feedback I would really appreciate it! The goal was to have a chat command that would give points to a player and would save when the player left and comes back even on a new server (Data Save?). Example i would say [LevelGuest3 giving the guest 3 points.

local groupId =
local dataStore = game:GetService("DataStoreService"):GetDataStore("UserCredits")

if game.CreatorType == Enum.CreatorType.Group then
    groupId = game.CreatorId
elseif game.CreatorType == Enum.CreatorType.User and groupId < 1 then
    local hint = Instance.new("Hint",game.Workspace)
    hint.Text = "YouFoundMy Leaderboard - Uh oh! Group ID was not found! Please try again!"
    game:GetService("Debris"):AddItem(hint,30)
end
game.Players.PlayerAdded:connect(function(player)
    local stats = Instance.new("IntValue")
    stats.Name = "leaderstats"
    stats.Parent = player

    local credits = Instance.new("IntValue")
    credits.Name = "Credits"
    credits.Parent = stats

    if groupId > 0 then
        local rank = Instance.new("StringValue")
        rank.Name = "Rank"
        rank.Value = player:GetRoleInGroup(groupId)
        rank.Parent = stats
    end

    if dataStore:GetAsync("Key" .. player.UserId) then
        credits.Value = dataStore:GetAsync("Key" .. player.UserId)
    else
        credits.Value = 0
    end

    credits.Changed:connect(function(save)
        dataStore:SetAsync("Key" .. player.UserId, save)
    end)
end)