How to get the exact size of the cursor

(I'm a beginner)

I want the player to hold right click, and allow the camera to pan around as they move the mouse, and when they stop right clicking the character locks to the cameras rotation, and the camera stops rotating. The issue is that when the player right clicks, the cursor locks to the middle of the screen and doesn't go back to its original position when done.

So I want to make a pretend cursor that stays at the exact position the actual cursor was at before the player used right click, then after the player is done right clicking the fake cursor goes invisible and the real cursor is set back to its previous position, instead of the middle of the screen.

How do I make the fake cursor the exact size of the real cursor?