Sim started modelling in 2014 for a local fashion brand, Love, Bonito's store online and was first runner up in New Paper New Face. In 2017, Sim made her acting debut in her first dramas, appearing in Dream Coder, The Lead and When Duty Calls in supporting roles. Sim starred in a short film titled Down The Rabbit Hole, which was created by the Central Narcotics Bureau (CNB) to remind young people of the hazards of drug abuse.
