N1 and N2

[Tu.114]

Before you begin with airplane type specifics, you really ought to come to grips with the underlying theory.

Looking at the level of your questions, Wikipedia might help you get a general understanding of these systems. As soon as you have read up on this and have further questions, by all means do come back here.

https://en.wikipedia.org/wiki/Airbreathing_jet_engine

https://en.wikipedia.org/wiki/Pack_(aircraft)