How to have draw turned off as default when email attachment - IPad Pro

I use my Apple Pencil similar to a mouse normally so I do not smudge up my IPad.  When I open a PDF as an email attachment, the Apple Pencil immediately draws on the PDF rather than letting me move the PDF as if I was using a mouse.  I would rather turn draw on when needed rather than having it automatically on.  I do not know how to turn draw off within an emailed PDF.  I do not know how to turn draw off as a default?

Any advice?