for whatsapp I think the files are prefixed with “wa” or something
and actually you could check the default filename formatting of real pictures and filter out all others (to put in a different location)
from this you could also check the size/ratio: pictures you took are usually not scared shaped, and definitely not in a gif format
filtering those out might already reduce the manual work
(for the last thing, IMO those photos are still part of your life, maybe put them aside but don’t delete things you could regret later, but that’s really up to you and your feelings)
for whatsapp I think the files are prefixed with “wa” or something and actually you could check the default filename formatting of real pictures and filter out all others (to put in a different location)
from this you could also check the size/ratio: pictures you took are usually not scared shaped, and definitely not in a gif format
filtering those out might already reduce the manual work
(for the last thing, IMO those photos are still part of your life, maybe put them aside but don’t delete things you could regret later, but that’s really up to you and your feelings)