changsha to zhangjiajie or fenghuangzhen?

No, the bus to Fenghuang will not pass Zhangjiajie. As for your trip, I suggest you go and visit Zhangjiajie first and then from Zhangjiajie to Fenghuang.

From CS city to Zhangjiajie, you can take a bus at the local West Bus Station. Upon your arrival at Zhangjiajie Bus Station, transfer to another bus to the scenic area directly.

Well, from Zhangjiajie City Central Bus Station to Fenghuang, there are two direct buses, departing at 08:30 and 14:30, and you can reach within 4h.

thanks .
Is it convenient for us to move around in the entire zhangjj scenic area if we were to stay in ZJJ National Forest Park rather than Wulingyuan ? How do i go from National Forest Park to wulingyuan ? as for the entrance fee 3 days RMB 248 , is it valid for all entrance to the park ?

Yes, dear. It can be convenient to travel around to stay at ZJJ.
Actually, the National Forest Park belongs to Wulingyuan Scenic Area. You can walk around to have a visit or take the scenic area eco-battery for sightseeing.

As for the entrance fare, you are right that it is valid for all entrance of parks within 3 days.