Can i travel from Ruili to Kunming by bus? How much would it cost for ticket fare?

Yes, you can take a long distance bus from Ruili Bus Station to KM directly. As I know, the ticket fare is CNY331/person and this trip will take around 12 hours. I am afraid there may be not many people speaking English. Generally, you can ask help for the hotel staff. May I have the specific address of the Central Commercial Area that you have mentioned? Then I can find the exact hotels for you.