Not that it makes any difference but I have drums all around. I know how they both work. You push the pedal and the bus stops. I even understand the difference in the design of the 2 systems but knowing that doesn't help me stop either. It's still all about the pressure on the brake pedal that makes me stop.
I know much more about my coach than I need to explain here as the OP was scared to drive a coach with air brakes and my response was accurate and welcoming. Get in the coach and go drive. That's all he needs to know about driving that kind of coach for the first time. With time, he will learn more just like the rest of us.