Q: i back my photo to my pc and how do i import back to my iphone?

If you backed up using iTunes backup then you would do a restore using the instructions in the iTunes section Transfer content from an iPhone, iPad, or iPod touch to a new device - Apple Support

Note that backed up photos are not viewable on the computer -- the backup can only be used for doing a full restore. Also note that the restore will completely replace the data on your current phone with the contents of the backup.

If it wasn't an iTunes backup, but you imported the photos to your computer (i.e., you could view them on the computer -- which is something you can't do with a backup) then you can sync them back to the phone using the following procedure: Sync photos from your computer to your iOS device using iTunes - Apple Support

YYou don't need to and probably shouldn't post your IMEI number on a public forum.

questionasker3 wrote:

 

YYou don't need to and probably shouldn't post your IMEI number on a public forum.

Good point -- I didn't notice it until you posted this -- I will report it to the hosts for removal.