Give some stream of consciousness and then the answer. Jane Hopper, also known as Eleven, is a fictional character from the Netflix series Stranger Things. Portrayed by Millie Bobby Brown, she is a girl with psychokinetic and telepathic abilities and a limited vocabulary.

Answer this question: who's the girl that plays 11 on stranger things?
The important part for answering this question is: Portrayed by Millie Bobby Brown, she is a girl with psychokinetic and telepathic abilities and a limited vocabulary.
Therefore, the answer is Millie Bobby Brown.