are photos stopred in mor than on spot on my mac

It depends. In addition to the local Photos.app album various cloud services (iCloud, WhatsApp, Google Photos, Dropbox, Microsoft, etc) might propose storing photos also in their services. I usually try decline them because I already have headaches caused by duplicates from other sources (family and relatives using those services and sharing images with stripped metadata) anyway. Despite those precautions I occasionally spot a duplicate with somewhat different date and then I have to compare which one is the best "original" and what date & time to use...

By default, no. They're all in your Photos Library. Other arrangements are possible but it would take deliberate action on your part to make that happen.