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If I understand correctly, you want to have a set of fields that can be repeated quickly if necessary?
The Configurable List Widget may prove useful for your form.
This widget allows the user to add another set of fields by clicking one button. Here's a guide on how to add the widget to your form: How to Add a Widget to your Form
Here's a demo form so you can see the widget in action: https://form.jotform.com/60417580570959
If you like, you can clone it to your account by following this guide: How to Clone an Existing Form from a URL