Flying tips!

La

I'm going to Hong Kong from the east coast at the end of June. It will be my first time flying as an adult. I believe I'll have business class (didn't buy the tickets so I'm nog 100% sure) and I'm completely lost. I have no idea what to do as far as bags and everything. The people I'm going with will help me out but if there were any tips you have, especially for a long flight, they'd be appreciated!!