I want to visit China Medical University, I live in UAE, Can you suggest me air/train route?

You can fly from Dubai to reach Guangzhou and then take a flight to reach Nanjing.
If you want to go to the Xuanwu Campus of that university, you can take the airport shuttle bus to reach local railway station and then take taxi to reach your university.
If you wan to to the Jiangning Campus, you can reach the local railway first and take the local subway line 1 to reach Zhongguo Yaokedaxue Station (China Medical University Station) directly.

If you want to go to the China Medical University in Sy, take a flight to Germany, Lufthansa has a direct flight to Taoxian Airport. Or fly to Seoul or Beijing and connect - many flights to SY city.

From Taoxian, take the airport bus (about 15RMB) into the city and then get a taxi to China Medical. It's near Zhongshan Square.
But remember, China Medical U. like many other universities is decamping to the far out suburbs, so you better check to see if you will be living in the Zhongshan Square campus or in far-outs-ville.