By Train:
From the airport, the train service departs from Flughafen Ber – Terminal 1-2, there you have 3 train services.
Fast option: you can take the ODEG or the Deutsche Bahn Regional train service to Berlin Alexanderplatz (S+U Alexanderplatz Bhf). These services depart hourly and will take about 28 min.
Slow option: The S-Bahn train service to Berlin Alexanderplatz (S+U Alexanderplatz Bhf) will take about 42 min and departs every 20 min.
Approx. price = 4-10 euros

All the above options are about a 15 min walk from the station or alternatively you can take a short taxi drive from there to the hotel.

By Taxi:
By taxi the journey will take about 35 min depending on the traffic.
Approx. price = 60-80 euros