Thank you for the information. I have tried but am still somewhat confused.
I placed the “encrypted” directory which contains the .gpg files and the secret_key.txt file into a directory on my local machine.
I typed from the link you provided:
export PASSPHRASE=$(cat secret_key.txt) and pressed enter. I typed PASSPHRASE rather than a particular passphrase - is this correct?
Then I typed:
sudo -E duplicity restore file:///directory/encrypted /home/user-data/
It seemed to work as the screen displayed: “Synchronising remote metadata to local cache…”
This creates a .gz file in the ~/.cache/duplicity/ directory. However, after running gunzip, I am left with a binary .sigtar file. What does this mean and is this the backup?