Customize a POS php code to enable restaurant style

on [login to view URL] i enable park orders per customer and enable change customer while order is added. example 1. customer 1/table 1 order 3 tems 2. i can change to customer 2/table 2 and add orders too 3. products are cleared per customer/table until payment is done. i would like a restaurant style where customer can order food collectively. make a change table function