That link is how to transfer a 2018 return that is on your computer into the 2019 online version. But it even has a typo. The first sentence should say a file extension.tax2018 (not .tax2019).
The user wants to download the Desktop program not use the Online version.
There should be a card in the CD case that says how to download it and you will need the 14 digit code from it to enter.
How to install Turbo Tax if you don't have a CD drive
https://ttlc.intuit.com/community/installing/help/i-bought-the-cd-but-my-computer-doesn-t-have-a-cd-...
