Buy Subnautica Pc and PlayStation?

I recently bought Subnautica for the pc. If I want to play it on the PlayStation 4 do I have to buy it extra or can I sign up somehow?

This is not going to work.

You have to buy a separate "original" for both systems.

Why do you want it for the PS4?

Is your PC monitor too small?

Then hang the PC on the SmartTV.

No, I just go back and forth a lot and have only one on the PC and on the other side of the Ps4 had hoped that would go.