The Playstation 4

I forget how this all works as I don’t us the PS4 all that much.

I have a profile on my PS 4 and it’s tied to a playstation account online. I want to create a profile for my son. He doesn’t play online multiplayer. Up until now he just uses my profile. Is there a benefit for him to create his own profile? His own set of save games I guess would be one, anything else? If he has his own profile, he’d get to use my PSNow or PS Plus if I got it, right?

Does PS Now work well? I’m looking for some stuff for my son to play and that would be a quick way to get access to some games. Would I be better off with PS Plus?

Thanks