Complex sentence: When her acting career failed to take off, at age 19 she worked as a waitress at Red Lobster in the Bronx but was fired for discourtesy to customers; she said she was fired from "at least fifteen jobs" for similar reasons.
Split into simpler sentences: When her acting career failed to take off, at age 19 she worked as a waitress at Red Lobster in the Bronx, but was fired for discourtesy to customers. She said she was fired from "at least fifteen jobs" for similar reasons.