10hrs stopover in Beijing

Yes, you can tour around the Forbidden City in these 10 hours.
From the airport, you are suggested to take a taxi to the scenic area directly. It takes around 25 to 30 mins. The fare is CNY 90 to 100. Then you can use 5 to 6 hours to tour around. After that, you can go to Qianmen Street to eat some local snacks if time permits. Go back to the airport by taxi. In general, you need to arrive at the airport 1.5 to 2 hours in advance. Have fun!