Lets say you created a form for a customer to pay their bill online and you wanted to give them a link with the amount pre-typed in. You would find the Field Name and add it in the URL.
Example: https://cmsmax.com/contact?name=Sam when you click this link, it adds "Sam" into the form field for the name.
On the form fields area, you will see an identifier. Add this like the example string above.
