Has anyone gifted a digital preorder ps4 game on amazon?

I'm trying to buy an upcoming PS4 game for some friends. Has anyone preordered a digital download game on amazon and if so do they just give you a code that you can use on any ps4 or do i have to sign in on PlayStation network and link my amazon and psn? Trying to gift two of my friends the upcoming call of duty ww2 game. Really wish the play station store would let you gift games to other PSN accounts. Any help would be appreciated.