I had tried upgrading my MacBook Pro to Catalina from Mojave a couple of times on my own, but always got stuck on a 'could not be verified' error at the very end of downloading the said upgrade. Finally I decided to get it done at a verified Apple Service Centre. I have backups of my important documents on iCloud as well as a Time Machine backup for everything on an external hard disk.
I had submitted my MacBook Pro to the Service Centre yesterday and got it back today. The upgrade to Catalina is perfect, but I've lost all my data and applications. Even the user profile that I was using is nowhere to be found.
Now iCloud is automatically restoring some of the documents that I had backed up, but the applications/software that I had installed are completely lost. I do have a Time Machine backup, but I am not sure how I restore to that one. Moreover, restoring would take me back to OS Mojave, I think.
Is there any way I can keep Catalina but get back my applications/software from Time Machine?