12 hrs layover in Kunming

I'm flying from Yangon - Kunming (12 hr layover) - Shanghai - Paris. Do I need to claim my luggage at Kunming as next destination is Shanhai and they take it as a domestic flight? I'm flying with China Eastern Airline.
How can I get access to Wifi for the whole night? Alternatively, how can I buy internet data package?

Thank you so much in advance!