Choose File > Open and open the PDF file you want to convert.
Open the Forms panel in the Tools pane.
Click Create in the Forms panel.
In the Create Or Edit Form dialog box, select Use The Current Document Or Browse To A File. Then click Next. Select Use The Current Document and click Next.
Acrobat analyzes the form and adds interactive form fields. When finished, Acrobat alerts you that you are in Form Editing mode.
You can review the fields Acrobat has created and manually adds fields, if necessary.
Click OK to close the Form Editing dialog box.