i would like to know how much it will cost for me to go to yulin Shaanxi from guangzhou

The best way for you is to fly from Guangzhou to Xian and then take train from Xian to Yulin. As to the airfare, you can check this webpage: https://www.travelchinaguide.com/china-flights/ . Well, for the train ticket price, you can look up this page: https://www.travelchinaguide.com/china-trains/ .