how to get to wax museum if we were in shamrock hotel in HK? is it cheaper to ride on a taxi or in a bus?

From your hotel, you can walk to reach Jordan Station where you can take the Tsuen Wan Line to reach Central Station. Get out of the station from Exit J2, you can walk to reach Garden Road to find the Peak Tram Station. There you can take a tram to reach the Peak to visit the wax museum. The MTR fare is around 9HK$ per person.
I am not very clear about the taxi fee from your hotel to the peak.