Do I need to buy a POS machine from you?

No, we do not sell hardware. An iPad, an iPhone or any Android tablet or phone runs it. A proper POS terminal such as a Sunmi or an iMin works with its built in printer and drawer port. An ordinary tablet with a network printer works just as well, and from an Android device a Bluetooth printer works too. Your menu is already in the system, so the real setup work is adding the people who will use it and giving each one four numbers.