VCDS

So just curious, my Ross-Tech cable is arriving tomorrow and I already have to app on my computer ready, but the guy at the shop last time was just breezing through windows last time I was at the shop and I have no idea what to really do. I know to open the engine section and I am sure I can find the button to watch the sensor outputs but what are all the sensors under? Aren’t they different blocks like 01, 02, 03, ect? Is there a list of all the blocks or whatnot and what they do?