if i don't follow tour package, do you think i can manage visiting kunming by myself?

Well, of course you can manage, on the condition that you made a very good preparation for the trip.
Don't worry! You will meet some people or the airport staff who speak English.
As for the local Muslim Food, you can certainy get some, such as the Lanzhou Lamian Noodle around you, Xingrenyuan Halal Restaurant at No. 273, Xichang Road and Xingren Halal Restaurant at Dianchi Road of Xishan District.