I am curious about how powertrain behaves the following situation

2WD mode
Does the front and rear drive shaft rotate?
How is transfer case working in this mode, does it just leave
the front output rotate freely or it cut its connection to front axle?

Neutral mode
Does the front and rear drive shaft rotate?
Where does the cut of engine torque happen? transmission, transfer case, drive shaft or
wheel?

Shift Automatic transmission to parking state
Where does the brake apply its force, on wheel, axle, drive shaft or transfer case

Apply hand brake
When does the hand brake apply its force, on wheel, axle, drive shaft or transfer case

2WD mode

Yes, the JK has a live axle and everything rotates at the same speed 100% of the time.

Neutral mode

Neutral means the input shaft rotates and the output shaft does not under power. i.e. Transmission in neutral power disconnect is in transmission, transfercase in neutral the power disconnect is in the transfercase.


Shift Automatic transmission to parking state

No brake is applied. A parking shaft meshes with the output shaft of the transmission. So the output shaft cannot move because it is mechanical bound (it can under extreme force).


Apply hand brake

The hand brake is the emergency brake and activates the rear brakes only via a cable (located on rear axle at each tire). Totally seperate from the hydraulic brakes of the pedals.