how to set an end date

Hi,

You can use our DateTime field. It's under the Quick Tools in the form builder:

Or, you can use our Date Difference widget: http://widgets.jotform.com/widget/dates_difference. Here's how you can add a widget to your form: https://www.jotform.com/help/252-How-to-Add-a-Widget-to-your-Form.

Thank you!