I've installed Ubuntu Mate 18.04.2 to its own 40GB partition on an 80GB HDD. The computer is online, and I've updated Ubuntu with all offered updates.
I want to run
ddrescue to copy files from an ailing drive to a new one.
Both drives are the same size. Both will be slaved into the system.
I know how to open the Terminal but I'm not sure what commands to use to install
ddrescue and its GUI. The actual copying, I think I can handle.