Pop-up help instructions?

Is it possible to insert a field to show pop-up help or instructions for the form?

Yes, it is possible to insert a pop-up modal.

You can check this guide for the step by step instructions.

-How-to-Add-a-Pop-Up-Modal-on-your-Form

Here is a demo of a pop-up modal.

https://form.jotform.com/70331350848958#close

Please let us know if you have further questions.