Manila-Guangzou-New York. Can I ask what are the things that I need to do?

Hi. I will be travelling from Manila to New York with a connecting flight in Guangzhou. My connecting time is 3h50. I believe that my checked-in baggage will be automatically transferred to a boeing plane. Can you kindly guide me? As this will be my 1st time ti travel alkne with a comnecting flight. Btw, I booked a my flight in csair.com (China Southern Airlines) Thank you so much!

PS. What about the allowed number cigarette as well? I've read a lot of blogs but no definite answer. Some says 200 sticks. Some say 400 sticks. Or will this even matter sonce it's just a connecting flight? Is there any form I need to answer for my flight from Manila to Guangzhou?