Save each file on your USB and transfer them to Zorin OS.
Save them as they are in your Downloads Folder.
Open a terminal and Change Directory (CD) to that folder
cd ~/Downloads
Now run the install command to install all the packages at once:
mark@mark-main-PC:~$ uname -a
Linux mark-main-PC 5.11.0-27-generic #29~20.04.1-Ubuntu SMP Wed Aug 11 15:58:17 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
mark@mark-main-PC:~$
mark@mark-main-PC:~$ uname -a
Linux mark-main-PC 5.8.0-050800-generic #202008022230 SMP Sun Aug 2 22:33:21 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
mark@mark-main-PC:~$
I was given 2 options, 5.8 generic or 5.8 recovery mode. i fired it up in generic and it is still the same
I built mine more than 5 years ago.
The problem/advantage of Linux is that it is soooo efficient with resources and makes me feel less need for upgrade.