from shanghai airport which bus number go to shanghai bullet train station.

There are two airports in Shanghai, one is Hongqiao and the other is PVG, all international flights use PVG. And there are three railway station in Shanghai, Shanghai station, Shanghai Hongqiao station and the Shanghai South station.
From PVG to Hongqiao station, take subway line 2 to Eastern Extension and get off at Guanlan Road station to connect subway line 2 to Hongqiao station, exit C. Or, you can take Maglev train and get off at Longyang Road station and then connect subway line 2.

From PVG to Shanghai station, as mentioned above, when you take subway line 2, then get off at Renmin Square, where you can change Line 1, exit 2.

From PVG to Shanghai South, you can take airport shutte bus No. 7.