She attended St. Aloysius Gonzaga Secondary School where she played four sports, including basketball, hockey, soccer and softball.

[1] During the 2015–16 season, in her senior year, she recorded ten goals and 15 assists in 33 games and helped Quinnipiac win the ECAC Hockey tournament for the first time in program history.

[3] On October 10, 2015, in a game against Maine, she became the third player in program history to record 100 career points.

During the championship game she assisted on Laura Stacey's game-winning overtime goal to help the Thunder win the Clarkson Cup.

[21] On April 20, 2024, she signed a one-year standard player agreement contract with Boston.

[23][24] Kosta represented Canada at the 2011 IIHF World Women's U18 Championship where she led the team in scoring with five goals and three assists in five games and won a silver medal.

[26] In addition to her professional ice hockey career, Kosta is a full-time chiropractor.