How do I add more products to my payment field

I am creating a lunch order form from different providers and would like parents to order selection from each provide and then provide a grand total of what they need to pay

For example

Ricci

Cheese pizza  April 5  1 x 2.50

Bertoni

Pasta  April 6  1 X 6.00

Total $ 7.50

To add more products, while editing your form, click on the payment field and then click on the little magic wand icon in the top right of the field.  That will open the setup menu for the payment field.  Additional products can be set up from there: