Question: how to install a dmg file on ubuntu?
Answer:  Install hfsprogs which enables operation with HFS and HFS+ on Linux via ports of mkfs and fsck. sudo apt-get install hfsprogs.
 Mount or remount the HFS+ drive. Aug 26, 2018 Mount the DMG file and install the app on your computer. ... 
 If the drive is partially corrupted or was unmounted with an error run: