1. Depending on where you're located, there are Confucius Institutes where Chinese Language is usually free. Also - depending on your age - you can get scholarships to study in China through the Confucius Institute and other organizations. You can "try" to contact the Chinese Embassy or Consulate in your home country for information or just search for them online.
2. Yunnan University's website:
ynu.edu.cn - there's an english button somewhere on the site. Contact the university's Foreign Affairs Office for the questions you have regarding classes, student visas, and tuition. Please remember - you can NOT work part time as a student in Yunnan, but you can provide non-professional english language lessons on an ad hoc basis. Rules regarding physical security and common sense apply.
Most probably you will be exiled to the campus outside the main city, Chenggong, which isn't too bad AND you can take the university bus into town - just remember to catch the last bus or subway home or you're stuck in the city (or LONG cab or Uber drive back to campus). University food is university food - edible, predictable, and after 30 days - boring - but if you're not a foodie, it's fine. The campuses generally also have Islamic cuisine for those who need/desire Halal (spelling?), which is a welcome change from the usually heavily overspiced EVERYTHING.
Kunming is generally safe, but if you're young and female, exercise common sense or you may be molested. China's heavily congested - lots of nutty people around if you stay long enough or put yourself into compromising situations.
You will find MANY foreign nationals studying in Kunming - regardless of university - with increasing students from the Belt & Road Initiative (BRI).
Best regards, stay safe, and enjoy the wealth and diversity of culture and history this province and the surrounding provinces and countries provide.
Thanks to the US Trade dispute - the CNY has devalued to roughly USD 1 ~ CNY 7 as of yesterday. So your USD, EUR, AUD, JPY, will stretch ≥10% further than last year.
Also - once you get settled WITH a bank account - sign up for WeChat, add your bank account to WeChat Pay, then you can fumble your way through online food deliveries - to include US fast food, such as KFC, MacDonalds, Burger King, Pizza Hut etc. Beware Kunming burger joints - their fare is frequently spicier than most normal humans can tolerate.