Can I give users an option to save and return to a form in progress?

There are a couple different ways to allows users to return to a partially completed form to finish at a later time. 

The first takes a bit of setup and requires multiple pages in the form:

https://www.jotform.com/help/97-How-to-Save-Forms-and-Continue-Later

The second is much easier to set up, but requires allowing for partial submissions to be entered and completed:

https://www.jotform.com/help/40-How-to-Let-Users-Update-Their-Form-Submissions-at-a-Later-Date

I tend to prefer the second.  It is quite simple and allow users to make multiple updates and edits.