Can I recover photos if it didn’t back up in iCloud?

Please check the following

1. If you sign out of Apple ID sign backing with another Apple ID after you had turned on Messages in iCloud & iCloud Photos, your content is safely stored in iCloud and is available on all devices that use the same Apple ID.
2. If you have restored your iPhone with a backup that does not contain the Photos that you are looking for then please look for the correct backup on your PC/Mac --> Locate backups of your iPhone, iPad, and iPod touch - Apple ...
3. Do you have a correct backup (iTunes) --> Restore your iPhone, iPad, or iPod touch from a backup ...
4. Probably you may have un-synced photos with Mac / PC, sync them again
   1. For PC: --> Sync photos in iTunes on PC with devices - Apple Support
   2. For Mac --> Sync photos between your Mac and iPhone or iPad - Apple ...
5. Have you ever imported your photos to Mac/PC and used "Delete After Import" --? Transfer photos and videos from your iPhone, iPad, or iPod ...
6. If not found anywhere, have you ever uploaded them to any Cloud Drives (iCloud Drive, Google Drive, OneDrive, DropBox, Flickr, box, AmazonDrive, Adobe Creative Cloud etc)

You don't. If they were not backed up, they're gone.