In his career, Stupak has participated in a number of competitions including the European Individual Chess Championships, World Junior Chess Championships, European Youth Chess Championships, and the Belarus Chess Championships. He has also competed in the Chess World Cup 2015 and 2017.

Stupak's style is characterized as aggressive and dynamic. He is known for his tactical acuity and good endgame technique. Outside of competitive chess, he coaches the sport, focusing on young and promising talent.