Maybe it is a nonsense question, but I would like to format my external HD which contains plenty of files and directories, the HD format is NTFS, if it is possible I would like to format to ext4 but keeping one directory and its files intact. I know that I can backup it before formatting. Is it possible ? I'm running Xubuntu 16.04.5 and this external HD was originally recovered from an old netbook running Windows XP. Thanks, Vladi
Nope. If you format a partition that contains files, the operation will clear out all of the files.
What you COULD do is use gparted to shrink the ntfs partition on the external drive, then create a new ext4 partition in the newly created free space (again using gparted), then move the files from the old NFTS partition to the new ext4 partition. Once you've done that, use gparted once again to remove the ntfs partition and to grow the new ext4 partition to fill all of the unused space.