A:AnswerYou should be able to fax without internet as long as you have a working landline. That is my experience with the TR8520 and I imagine it is the same with the TR8620.
A:AnswerYes. Go to this page for downloads: https://www.usa.canon.com/internet/portal/us/home/support/details/printers/inkjet-multifunction/tr-series-inkjet/pixma-tr8620/pixma-tr8620?tab=drivers_downloads
A:AnswerI have run this printer wirelessly from my Android Samsung Galaxy tablet as well as from my wifes' Apple Macbook Pro with no proble except to select the proper printer.
A:AnswerYou can scan multiple pages. I just put a couple of 8 page documents (single sided) in the auto feeder and it did a great job scanning multiple pages and keeping them in a single document.