Dynamic order form

I have an extensive paper order form with many options, and I would like to transfer it to an online form. Rather than include all options directly on the form which would make the form rather large, I want to make my form dynamic with accordion dropdown fields. In this case, we're offering gift cards to purchase for fundraising, and they are divided into categories, retailers, and amounts. I would like for a user to be able to select their category, then the form shows the retailers in that category, and when they select a retailer, the form shows them the $ amounts available for that retailer.

It would be great if the dropdowns could reference a csv file so I don't have to input every item and combination in the form.

When a user has chosen an item, they could click to add another item and choose from the dropdowns again.

I saw several options in the widgets which look helpful, but I'm hoping you can provide some advice.

We have this dynamic dropdown widget - Dynamic Dropdowns

You can also check Grouped Values Dropdown widget. 

However, with those widgets, the users will not be able to add another option. If you want to allow them to select more options from the dropdown field you can use Checkbox in Dropdown widget or you can use Configurable list widget. With this widget, the users will be able to dynamically add new fields to the form. 

How to Set Up the Configurable List Widget

If you also want to perform a calculation inside of your form, please note that you will not be able to assign calculation values to the widgets I provided above. The calculation values can only be assigned to the basic dropdown field. 

How to Perform Form Calculation Using a Widget

However, you could perform a calculation with the conditional logic, with some of the widgets I mentioned above. It is not possible to perform a calculation with Configurable list widget. 

How to Insert Text or Calculation into a Field Using Conditional Logic

You can add a downloadable CSV file to your form - How to Add a Downloadable File to Your Form

Hope this will help. Let us know if you need further assistance.