If you arrive at the Railway Station in the early morning, you can take bus at the square of the railway station heading to Tangkou. Then transfer to another bus to the spot. There is no bus number, you may ask the staff at the station upon arrival. Or, if you take taxi directly, the fare is around CNY100-CNY120 per cab.

how long do you need for mountain ? climbing ect if I went straight from the train station

The bus ride from railway station to Tangkou takes around one hour. It takes about 5 or 6 hours to climb from the foot of the mountain to the top. If your time is ample, I suggest you stay overnight on the mountain to see sunset or sunrise. This is also a popular way for most tourists. If not, you may take cable car instead and the cableway stops running after 16:30.