JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
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 have inspected your form https://www.jotform.com/61647120203140 and only widget you have inside of that form is "Image Upload Preview". Do you want to change font family and font size of upload button text?
If that is the case you can add this CSS code to you widget Custom CSS field.
font-family: arial, helvetica, sans-serif;
If you want to change font in some other widget, please provide us ID of the form you are working on and tell us text of which widget you want to change.
Let us know if you need further assistance.