My friend wants to join me on trip to china. I am in usa she from india. Can we share room in Beijing?

Can she pay in Indian currency and whaqt would be her cost.
If I get a return ticket to beijing and back, and trip ends in Shanghai, what internal flight can take me to beijing, and what time is the International flight To Usa. Is the timing feasable?.
What beijing airport must I arrive at. What is the Shanghai airport I must leave from, if I find air service from there.
What are the taxes I pay at airport,each timeIn US currency or Chinese currency. How much should I come with for taxes.