Bee Tee

Hello Everyone New to this forum and unfortunately my first post is to ask for help.I have a 2017 allroad A6 i have registered with "my audi" and decided to try to update the navigation system it tells me i must download installation software first. Well that where my problem begins how the blue blazes do you do this please forgive my thickness on this one i just can not get this to down load any help would be very much appreciated Regards Beetee