[10][11][12] Her acting career began when a casting director found her photos and encouraged her to audition for the film adaptation of John Green's novel Looking for Alaska.

[3][14] In 2018, she starred in two Netflix movies, Sierra Burgess Is a Loser[15] and Apostle,[16] and a Sky miniseries, The Truth About the Harry Quebert Affair.

[19] She stars in the 2021 Amazon Prime Video film Birds of Paradise directed by Sarah Adina Smith.

[21] That same year Froseth played the protagonist, Coby Rae Dellum, on the first episode of the second season of the FX on Hulu series American Horror Stories which aired on July 21, 2022.

[22] Also in 2022 she starred in the Lena Dunham sex comedy Sharp Stick and Daniel Goldhaber's action-thriller How to Blow Up a Pipeline.