Create a plane at center of screen

Hey guys i am really new to max scripting and i am strungling to create a plane at the center of the screen . So, i just started with

Plane length:1000 width:1000 pos:[0,0,0] isSelected:on

But i wanted to change the pos:[0,0,0] to always create the plane at the center of the screen or on top of the mouse cursor.

Can anyone help me with that ?

Best regards