Guidance for live testing a portfolio of stocks

I have a subscription to IQfeed with allowance of 500 simultaneous symbols live streaming.

I would like to live test a trading system with buy / sell criteria, on these streaming stocks, live during market hours. All this with portfolio features, such as max number of positions etc.
I want the system to generate signals and simulate buy/sells in real time, then check result at end of day.

Could you please give me a 10000 feet overview on how to achieve this with AB, if possible?

I understand how to do this with the backtest feature, but not sure on how to do it on live data.