Sorry, but that is one convoluted mess, especially without punctuation, but I think I got the gist of it.
Simply do backups via Time Machine or
CarbonCopyCloner or
SuperDuper! and an external HDD or two.
A data recovery application needs to be run from a different HDD or SSD to scan any HDD or SSD to locate deleted, but not overwritten files, as deletion of files does not physically delete them, but the sectors they are stored in, get marked to free for writing new data, thus after an accidental deletion of a file or folder, and one has made no backups, it is best to leave the actual HDD as it is and use another HDD to install the recovery application on and run it from there.
Using partitions might work, I never tried it, but then again, I also have backups.
I have one 500 GB HDD for my photographs (digital and analog) libraries and editing documents, one 500 GB HDD with my personal video footage in an editing friendly format.
Both 500 GB HDDs get backed up to one 1 TB HDD via
CarbonCopyCloner.
And that 1 TB HDD gets backed up to another 1 TB HDD via CarbonCopyCloner.
Therefore I have three copies of my important data.