Edit form submissions for changes

when someone makes a submission and we find that something needs to be changed (such as the item ordered, etc) can we make changes to that submission or do we have to do a new form completely? 

You can edit submissions made to your form. The instructions on how you can do that can be found in this guide — http://www.jotform.com/help/325-How-to-Edit-Submissions-Made-on-Your-Forms

If you want to allow your respondents to edit their own submission, then you can follow the instructions in this guide — http://www.jotform.com/help/40-How-to-Let-Users-Update-Their-Form-Submissions-at-a-Later-Date

Feel free to let us know if you need any further assistance.