What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
If you want to show or hide products depending sections selected, then you will need to set them up in normal fields, using radio buttons, drop downs or check boxed:
You will need to also change the current settings on your payment field, and will need to use a widget too, the Form Calculation widget will help you to get the total amount and pass it to your payment field.
As I can understand, you want to separate your products in sections, then show them separately, here is a guide that may help you, so for example, if a category or section is selected the proper products will be displayed: How-to-Show-or-Hide-Fields-Base-on-User-s-Answer
Here is also a guide that will help you to pass the calculation value to the payment field: How-to-pass-a-calculation-to-a-payment-field
If you need some help when applying this to your form, please let us know, we will be glad to help you.