Newsome was born in Vacaville, California, and grew up on a ranch. She attended DePaul University in Chicago, where she studied theater. After graduating, she began her comedy career with the Second City improv troupe.
Newsome's first major television role was as Chelsea Leight-Leigh on Bajillion Dollar Propertie$. She also had a recurring role as Nina on The Comedy Get Down. In 2020, she began voicing the character of Beckett Mariner on Star Trek: Lower Decks.
Newsome is also a musician and is a member of the band Four Lost Souls. She is also a co-host of the podcast Yo, Is This Racist? alongside Andrew Ti.