how to take mtr from hk airport to argyle street?

Actually, you can take E21 to reach Mong Kok Market, Argyle Street or take A21 to reach Argyle Centre, Nathan Road directly.

If you want to take the MTR, you can take the Airport Express to reach Tsing Yi where you can change to Tung Chung Line to reach Lai King Station. There you can change to Tsuen Wan Line to reach MongKok Station. Get out of the station from D1, you can walk on the Argyle Street.