I could not use JInternalFrameForm
in Netbeans.
I did right click on my package and go new but I did not see JInternalFrameForm option.
The right click New menu only shows you options you have commonly used, or only several default options if you haven't used any.
to find JInternalFrameFrom, select the Other
Option on the bottom of the options,
Then type in JInternalFrame
in the search box of manually find the component inside the Swing GUI Form
folder.
see the image below