I'm flying with Air China for an International to International transfer flight.

I'm coming from the U.S. and have a 3hour40min layover in Beijing and will arrive at Terminal 3. I then have a connecting flight with Air China to go to Japan at Terminal International. I am not leaving the airport. I'm wondering if I still have to scan my passport and fingertips, go through immigration and if I have to fill out the arrival card. Also what to do for any checked luggage. As much details possible will be appreciated, thank you.