How do I allow my clients to edit their information?

Also, I need to add an option in the confirmation email my clients will receive so they can go back and edit and update their information. How can I add this option?

You'll need to add the {edit_link} tag in your email notification. Please checkthisguide https://www.jotform.com/help/40-How-to-Let-Users-Update-Their-Form-Submissions-at-a-Later-Date for steps on how to add that into your autoresponder.

Let us know if you have any questions or if you need further assistance.