how can i disable mouse cursor?

how can i disable mouse cursor?

and/or

showCursor show/hides the cursor while lockCursor prevents the cursor form leaving the window.

Visibility

While disabling the cursor isn’t really possible, it can be made invisible.

This can be done with the following code:

Cursor.visible = false;

Locking

Another method, that has a side effect of making the cursor invisible, is to lock the cursor to the center of the screen, this can be ideal when using mouse input for pan/tilt or pitch/yaw type controls, i.e. camera pan/title or spacecraft movements

Cursor.lockState = CursorLockMode.Locked

More info, including different lockstates and how to use a custom cursor, can be found here:
Unity - Scripting API: Cursor