Q: how i can get a photo i deleted from my iphone

If the photo was taken by the iPhone (and not copied to the iPhone from another device), then there are three ways:  1)  assuming you made an iCloud backup, and the photo was in the camera roll, then reset the iPhone (this erases everything) and perform a restore from iCloud.  Unfortunately, many users claim they lost photos when doing this (somehow the restore did not include all photos), 2) which is the general method, find the photos on the computer you synced the photos to (always sync iPhoto photos to a computer - also see 3), and 3) assuming you had photo stream working, then find the photos on the devices also connected to photo stream.