There is no way for TWS to determine "cumulative" anything -- that will be something different for every account, and even then, may differ for individual accounts from one instant to the next.
To close this "basket" as a whole:
1) investigate BasketTrader
2) load indidudual trades, pausing execution, and then Transmit All or Transmit Page as appropriate.
This would be a fine time for you NOT to trade your live account, but to bring up your PAPER account, and make it work there, first. Everyone has to make a first trade (of whatever type) sometime, but you are swinging a large-caliber weapon around, announcing "I don't know how this works."