How can my imported photos in my MacBook Air be gone?!!!

I can't find all my pictures from 2015 and up to last month. I do not have multiple libraries, I have not deleted them (as far as I know), they are not in the trash or in the recently deleted file. I logged into iCould my pictures are gone from there too. All my pictures are supposed to be uploaded to iCloud automatically and they are imported in to the default photo library. I do not have Time Machine set up. However, I do have copies of my pictures from the last time I copied them into an external hard drive in 2014.

The mystery is what in the **** happened to all my imported pictures I had in my MacBook Air? I have plenty of memory available in my laptop and I have not done a recent upgrade or anything like that. I'm running Sonoma 14.5. The last time I saw my complete library was around 10/12/25.

If there is program I can use to recover/find my photos that are missing, please advice .