The drag caused by the rotating propeller (or the propeller torque) acts opposite to the engine torque i.e. for the point of understanding if the engine torque rotates the prop clockwise the drag acts counter clock.
That's OK
The next bit's not quite right ..
the prop drag will be much lesser than the engine torque
We can't equate the two as they are are different - drag is a force while torque is like a moment. Better to say that the engine torque can provide the means to
(a) allow the prop to slow down (engine torque less than what is required to balance the prop disc drag loads so the prop decelerates until the drag loads are balanced by the engine torque)
(b) maintain an RPM (engine torque equals what is required to balance the prop disc drag loads)
(c) cause the prop to accelerate (engine torque greater than what is required to balance the prop disc drag loads so the prop accelerates until the drag loads are balanced by the engine torque)
but it reduces the thrust power as compare to the shaft power thereby reducing the prop efficiency.
I'd leave this bit out of consideration.