How can people see their own form after submitting

If I understood you correctly, you want that your users are able to see data they have submitted. You can achieve that by creating a form Autoresponder. When you create Autoresponder, your users will receive email with data they have submitted. Inside of this guide you can find how to create a form Autoresponder: https://www.jotform.com/help/26-Creating-a-Form-Autoresponder 

In case that you also want to allow your users to update their form submissions at a later date, please check this guide: https://www.jotform.com/help/40-How-to-Let-Users-Update-Their-Form-Submissions-at-a-Later-Date 

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