A 21-year-old forward, Chalupa spent the majority of last season with HK Hradec Kralove of the Czech Republic League where he skated in 50 contests and recorded 24 points (7G, 17A). His 17 assists shared first among HK Hradec Kralove skaters, while his 24 points ranked fourth on the club. He also appeared in two playoff games with HK Hradec Kralove during the 2019-20 season. Chalupa skated in one game with SK Kadan of Czech Republic-2 League on loan last season, where he notched a goal.
Over two seasons (2018-20) with HK Hradec Kralove, Chalupa tallied 38 points (11G, 27A) in 98 games and skated in six playoff contests. During the 2017-18 season, he made appearances with HC Plzen of the Czech Republic League, HC Stadion Litomerice of the Czech Republic-2 League, HC Slovan Usti nad Labem of Czech Republic-2 League, HC Klatovy of the Czech Republic-3 League and HC Plzen U20 of the Czech Republic U20 League totaling 16 goals and nine assists across 57 games.
A native of Prague, Czech Republic, Chalupa made his Czech Republic League debut during the 2016-17 season with HC Plzen, skating in six contests. He also recorded 62 points (31G, 31A) in 43 games with HC Plzen U20 of the Czech Republic U20 and nine points (4G, 5A) in five games on loan with HC Klatovy of Czech Republic-3 League.