I m going to tai tong country park in yuen long from Sheung Wan.

Here is the direction to Tai Tong Bus Stop:
take Island MTR line from Sheung Wan to Central, where transfer to Tung Chung line and get off at Nam Cheong. Then transfer to West Rail line and drop off at Long Ping. After that, walk to ng Cheong Path (near MTR Long Ping Station) to take bus no. K66 and get off at Tai Tong.
The whole trip takes around 80min and the fare is 25.4HKD.