Her father is of Mexican American descent and her mother is of mixed Mexican and Puerto Rican ancestry. She is the fourth of six children. She became interested in acting from the age of six. By the age of eight, with her mother's help and agents, Ortega began receiving auditions.
In March 2018, she joined the cast of the ABC television pilot Man of the House, playing the role of Elena who is described as "a beautiful and mean spirited only child, who doesn't adjust well to living with her cousins". The pilot was not picked up.
In January 2019, it was announced that she had been cast in the main role of Ellie on the second season of the Netflix thriller series You.