Hello belal104,
Thanks for reaching out to the Apple Support Communities. We understand you are looking for some help with your iPhone. We are happy to help provide some guidance.
Do you know if you have iCloud Photos enabled on your device? The iCloud Photos option makes it so your photos and videos are synced with iCloud instead of storing your photos and videos within a backup. So if you have this option turned on, your photos wouldn't be contained in the backup you restored to your device. Instead, they should start to download from iCloud directly once you sign in to your Apple ID on your iPhone. You can read more about that here:
Set up and use iCloud Photos
Let us know if you have iCloud Photos enabled in Settings > [your name] > iCloud > Photos. Also, was this backup that you restored an iCloud backup, or a backup you had created in iTunes?
Let us know and we will proceed from there. We hope this information helps.
Best Regards.