I'm a bit confused and not sure on the best way forward with this:

Looking at getting son a PS4 for Xmas - he currently uses my PS4 and i have set him up a sub account which he has physical and downloaded games and also all his saved progress files.

When he opens his Xmas gift and we start to set up the PS4, how will he be able to access all the stuff he had?

Or can he not?!