How do I remove the "enter" function that sends a form?

I have a lengthy form that people are accidentally sending via "enter" when they mean to be tabbing through the application.

Do you have a solution for this?

By "Enter" I think you mean the "Submit" button, right? I can see in your Franchise Application form, that none of the fields are marked as required. So the users can omit all fields and click on Submit.

Please note that if the Submit button is removed, then your users cannot submit the form and submission will not be recorded.

So an option here would be to set the fields in the form as required. You can decide which all fields you require as mandatory to be filled. Here I have shown an example of one field set  up as mandatory. Likewise you can set other fields as "required" based on your requirement.