Ryanair to Amsterdam. Which Terminal?

I have booked tickets with Ryanair to Amsterdam. I assume that the airport is Schiphol?

Does Ryanair use any particular terminal at Schiphol. I see that there are 3 Terminals under one roof? Is this correct?

I will be getting the train to the airport. Does it stop at any particular terminal. Is it a long walk from the train to the Ryanair departure gates?

Thanks

Yes it is Schipol airport. We travelled there with Ryanair in April.
Departures 3 will be your check-in zone for your return flight in Schipol and most likely the departure gate will be in the H pier, but that could change for several reasons. The H pier gates are quite a walk from the main 'holding' area of airside after security.
There is one train station serving the airport, and it is quite a walk from there to the departure gates but no better than getting a bus or taxi (or being dropped off as a kiss-and-fly).