How can we get to royal view hotel from hong kong airport by MTR?

Well, taking subways is not a convenient for way for you to choose.
There is no direct subway and you need to take bus and taxi.
Upon landing, take bus no. A31 at Airport (Ground Transportation Centre), get off at Tsuen Wan (Tsuen Wan West Railway Station Bus Terminus). The fare is 19 HKD per person. Then take a taxi to get to the hotel directly. The cab fare is about 50 HKD.