How can we remove any autofill prompts in the form?

We will have a registration desk with one computer and our jotform.

How can we remove any autofill prompts, so one person can't see the choices created from previous users data?

The autofill is disabled in the form. It is probably the auto fill of your browser that is enabled and saving the data in fields. Here are guides you can check to disable the default auto fill for browsers:

https://support.google.com/chrome/answer/142893 

https://support.mozilla.org/en-US/kb/control-whether-firefox-automatically-fills-forms