I need all photos from my gallery to the sd card and I don't know how to
Useless. None of this shows on my LG Optimus Zip. The answer must be for some OTHER LG phone.
Please make sure that you do have an SD card installed in the device. Once verified this you should just go to Home ➔ Apps Menu ➔ Gallery ➔ Select the pictures and tap on Menu (bottom of the phone near home button) Move/Copy to SD card.