Can I upload a form I want to use?

To my understanding, what you showed us in your screenshot is a PDF form, is that correct?

Do you want to turn that form into an online form? I believe the easiest way would still be is to create the form manually on the builder page.

Or, you can also check this website — https://www.jotform.com/fillable-pdf-form-creator/ if you want to turn that PDF form into a fillable PDF form.