How long it take to travel from Zhuhai(Gongbei port) to Shenzhen (Huaqiangbei) via bus ? How much ?

You can take the coach from Qiguan Gongbei Bus Station, get off at Luohu Bus Station first. The ticket fare is CNY 100 per person.
Then take subway Luobao Line to Grand Theater Station and transfer to Shekou Line to Hua Qiang Bei Station. It costs CNY 2 per person.