I did a back on my iPhone 12 Pro Max which was 200gb of photos but when I got my iPhone 14 pro max only 20 or so gb come on my device but however now when I got iPhone 13 Pro with 1tb I was going to back up my phone but it shows me 39Gb storage one I can’t see my old back up plus soo many important photos lost not in my current phone plz help
iPhone 12 Pro Max
You seem to be confusing several things that are unrelated.
You refer to (presumably) iOS backups, and some missing material, including photos. Please understand iOS backups do not include photos.
Backup methods for iPhone, iPad, and iPod touch - Apple Support
So it's important to understand exactly where your photos are/were housed. Perhaps you elected to use iCloud Photos.
If your iCloud Photos aren't syncing to your device - Apple Support
You seem to be confusing several things that are unrelated.
You refer to (presumably) iOS backups, and some missing material, including photos. Please understand iOS backups do not include photos.
Backup methods for iPhone, iPad, and iPod touch - Apple Support
So it's important to understand exactly where your photos are/were housed. Perhaps you elected to use iCloud Photos.
If your iCloud Photos aren't syncing to your device - Apple Support
Lost back up
