It is about 1.5 km from Belarus Station, the Moscow terminus for trains to/from Belarus (Minsk and Brest), Kaliningrad, Smolensk and international destinations including Vilnius, Warsaw, and Berlin, to the Novotel Moscow Center Hotel.
By taxi
Depending on the time of day, the journey by taxi will take a little over ten minutes, but should not cost more than $15. If you prefer, you can pre-order a transfer with a driver to meet your train here.
By metro
From Belorusskaya Metro Station (connected to the mainline station concourse), take the circle line and travel one stop clockwise to Novoslobodskaya, which is only 100m from the Novotel.