if i restore my iphone will i lose all my photos?

Restoring your phone erases everything, but you will be given the option to restore from a backup at the end to recover your data and settings so be sure to back up your phone before restoring. The backup will includephotos in your camera roll. Save any photo stream photos to your camera roll by opening your my photo stream album, tapping Edit, tap all the photos, tap Share, tap Save to Camera Roll. They will then be included in the backup.

And when I restore from backup, the photos will be stored in the Camera Roll too?

salonpas wrote:

And when I restore from backup, the photos will be stored in the Camera Roll too?

Yes. The backup includes camera roll photos, but not photo stream photos. If you want those to be included in your backup, save them to the camera roll.