As it is not your system disk, you may install
sudo apt install testdisk
Accept the first question (Create a new logfile). Then select the disk you want to recover - be very careful, as this may damage any disk if you do not select the right device!
Next select which type of partition table was (is) on the disk. Usually this will be "Intel PC partition". But testdisk tells you what type of partition table it did find.
After that, select "Analyze", then "Quick search". If the result is not what you expected, select "Analyze deeper" as the next action.
Some time later after having analyzed the disk you will be shown the result of the analysis. As this depends on your configuration, I cannot help from this point.
Nothing will be written to disk until you request to do so.
A good step-by-step instruction may be found on the testdisk wiki: