How to disable the "Enter/Return" button from submitting the form?

The form should not redirect to the thank you page until the person hits the submit button.  How do you fix this?  thank you.

That is the standard behavior and it is not possible to disable the "Enter/Return" button from submitting the form with in Form Builder and on standalone forms.

There are some possible workarounds. 

You can make your form fields required. You can also add a captcha field at the bottom of your form and make it required. 

How to Add a Captcha Field

Or you can embed your form to your website using Full Source Code and add custom script that will prevent that form is submitted when "Enter/Return" button is used. Form more details you can check this thread: https://www.jotform.com/answers/355370 

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