how to travel from hangzhou to hongcun to huangshan? i wish to travel by flight or train.

Huangshan is located between HZ and Hongcun. So my suggestion is that you travel from HZ to Huangshan first, and go to Hongcun. The distance from HZ to Huangshan is 132 mi (213 kilometers), so near that there is no direct flight. And there is no direct train either. So you shall go by bus.
You can take bus from HZ West Bus Station to Huangshan Scenic Area directly. The bus is available from 08:00 to 15:10. Bus fare is CNY110.
From Huangshan to Hongcun, you can take first take bus from Tangkou (near the south gate of the mountain) to Huangshan Tourist Distribution Center. There you can take bus to reach Hongcun directly.