Strange af problem ?!

What is your question?

My ac when turned off will still blow out the side vents, then when I close the side vents my defroster blowers start running ? I'm not sure if this can damage my car in the future . And ... When I turn my car off the ac will continue to blow for another 10-15 seconds . does anyone have an answer , I have high hopes for this vehicle and I want it to be perfect !