What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
I'm not too sure I undertand the question correctly. It appears to me you need the https url for your form.
You can obtain it by goignt to the Embed Form section of the Form Editor and clicking on the Secure Form checkbox, like so:
Do let us know if you need further assistance, below I'm appending the guide that describes how to go about adding forms to Facebook.