Newhook began playing hockey at the age of three. Until 2018, she played for the boys' St. John's Hitmen bantam AAA, serving as team captain in the 2017–18 season.[1] She then moved to the United States to play for the Bay State Breakers and Tabor Academy.[2] She committed to join Boston College in the United States for college hockey when she was 14, the youngest girl from Newfoundland & Labrador to commit to an NCAA Division I team.[3][4] She began studying at the university in the 2021–22 season.[5]
In her first NCAA season, Newhook finished ninth in Hockey East scoring, and led the league in goals (16), assists (13) and points (29) by a rookie player. She was consequently named the Hockey East Rookie of the Year, as well as to the All-Rookie Squad.[6][7] In her second year with the Eagles, Newhook recorded 19 goals and 14 assists in 36 games.[8] She was named to the league's Third All-Star Team.[9] In advance of her third NCAA season, she was named team co-captain, a rarity for a junior player that she professed to be "surprised" about, adding "I think that my teammates have a lot of confidence in me and that means a lot to me."[8]
International play
Newhook appeared at three selection camps for the Canadian U18 team, but did not make the final roster on those occasions. In 2022 she was invited to Hockey Canada's U23 development camp for the first time. She returned the following year as well, and this time participated in a three-game tournament against the United States in Lake Placid.[9][8]