How to get player in OnMouseEnter function?

Hello, I'm trying to make a TD game into an online version can get stuck with how to get the player identity.
The floor is made by cube and each cube has a script on it to check can the tower build on it or not.
I'm trying to get the player before the original cube function but I don't know how to pass check which player clicked on the cube and which player owned the cube.

Is it possible to have something like OnMouseEnter(Player player) to get the player value?
What should I do in this case?
Thank you