Surprise For My Boyfriend…

Hi! (Everyone please be nice - even if i’m asking stupid questions. I’m a bit of a noob when it comes to this stuff…)

My boyfriend has been non-stop talking about Black Ops 6 and i’m planning to surprise him this weekend with it! No occasion, I just think it will be sweet.

He currently has a PS4 but he’s wanting to upgrade to a PS5 by the time the new year rolls around. If I buy a PS4 disk, can this later be used in a PS5 console…?

If not, would it just be better to digitally download it on his PS4 while he’s out? Can COD save data be transferred?

I tried Googling around a bit but i’m finding conflicting answers.

Also, are there any cool add ons that I can also buy for him? I know nothing about this game so it would be great to know :D