Congratulations on your new iPhone! I understand that after restoring from an iCloud backup, your photos haven't loaded. I can understand the concern. I'll be happy to go over some information with you.
If you use iCloud Photo Library, they wouldn't be included in the iCloud backup, per About backups for iOS devices . All you would need to do is to turn on iCloud Photo Library by going to Settings > [your name] > iCloud > Photos, then turn on iCloud Photo Library.
If you aren't using iCloud Photo Library, please review the following information from, If iCloud Backup couldn’t be completed or you can’t restore :
If the restore process takes a long time to finish
Stay connected to a reliable Wi-Fi network and a functional power source until the process finishes. The time it takes to restore from a backup depends on the size of your backup and the speed of your Wi-Fi network.
Let me know if this information helps with your photos issue. Thanks for stopping by the Apple Support Communities.
Kind Regards.