Fields started high school at Lakeside Academy in Montreal in 2007. The following year she spent at Regina High School in South Euclid, Ohio. She spent her junior year at Oak Hill Academy in Virginia, where she averaged 26.5 points per game. She transferred to Mater Dei High School in Santa Ana, California for her senior year. Although she only played for Mater Dei for one year she made enough of an impact that the school retired her jersey at the end of the year. During the year she averaged just over 22 points a game to help the team to a 34–3 record, and a CIF SS Division 1AA state championship. She was named a McDonald's All-American and eligible to play in them McDonald's All-American game, the first female Canadian to earn such an honour.
Fields was a member of the Canada women's national basketball team which participated in basketball at the 2015 Pan American Games held in Toronto, Ontario, Canada July 10 to 26, 2015. Canada opened the preliminary rounds with an easy 101–38 win over Venezuela. The following day they beat Argentina 73–58. The final preliminary game was against Cuba; both teams were 2–0, so the winner would win the group. The game went down to the wire with Canada eking out a 71–68 win. Canada would face Brazil in the semifinal. Everything seemed to go right in the semifinal game. Canada opened the game with an 11–2 run on seven consecutive points by Miranda Ayim. Miah-Marie Langlois contributed five assists. In the third quarter Canada strongly out rebounded Brazil and hit 69% of their field goals to score 33 points in the quarter. Lizanne Murphy and Fields hit three-pointers to help extend the lead to 68–39 at the end of three quarters. Canada continued to dominate in the fourth quarter with three-pointers by Kia Nurse and Kim Gaucher. Canada went on to win the game 91–63 to earn a spot in the gold-medal game against the USA. The gold-medal game matched up the host team Canada against USA, in a sold out arena dominated by fans in red and white and waving the Canadian flag. The Canadian team, arm in arm, sang Oh Canada as the respective national anthems were played. After trading baskets early the US edged out to a double-digit lead in the second quarter. However the Canadians, spurred on by the home crowd cheering, fought back and tied up the game at halftime. In the third quarter, it was Canada's time to shine as they outscore the US 26–15. The lead would reach as high as 18 points. The USA would fight back, but not all the way and Canada won the game and the gold-medal 81–73. It was Canada's first gold-medal in basketball in the Pan Am games. Nurse was the star for Canada with 33 points, hitting 11 of her 12 free-throw attempts in 10 of her 17 field-goal attempts including two of three three-pointers. Fields contributed seven rebounds to lead the team and nine points.
