International flight to domestic flight as an international student

Hello, I am flying to China in August so that I can go to Xi'An and study as an international student for 4 years. My flight is from Athens to Beijing to Xi'an. The hours of waiting are 3 hours and 35 min. I don't know if they are enough. It is a connecting flight with Air China and my baggage is checked through, no need to do another check-in. If I get off the plane in PEK, where do I go for the departure for Xi'An? Also, how do I know if the baggage I checked in is found and inside the plane that I will take for Xi'An? Will someone inform me or something? Also, do I need to do the fingerprint process in PEK or I can do that at my destination, in Xi'An? It will be my very first time travelling by plane, not to say being in China for the first time, so, I would appreciate it if you could guide me for this specific travelling of mine.