She started her career in episodic roles in the television shows Cracked, Reign, Degrassi: The Next Generation, The Lizzie Borden Chronicles, and Coyote.
[3] In 2017, Forsyth appeared in the second season of the horror anthology series Channel Zero alongside Aisha Dee and Jeff Ward, in which she played the lead role of Margot Sleator.
[4][5] In 2018, Forsyth was cast to play the lead role of Gwen Strickland in the musical drama series Rise starring Josh Radnor.
[8] Forsyth co-starred Isabelle Fuhrman in the 2021 psychological sports drama film The Novice directed by Lauren Hadaway, where she played the role of Jamie Brill.
[10] In 2023, Forsyth was cast to play the main role of Linda in the drama series Dear Edward, based on Ann Napolitano's 2020 novel of the same name.