Bibeau, the Islanders sixth-round pick (178th overall) in the 2019 NHL Draft, established career highs in points (70) and goals (29) in 63 games last season in the Quebec Major Junior Hockey League. The Mercier, QC native started his fifth QMJHL season with the Quebec Remparts, who traded him to the Chicoutimi Sagueneens in December. When the QMJHL season was halted, the Sagueneens had already clinched the top spot in their division and Bibeau ranked third on the team in points, goals and assists (41). League-wide, he tied for 21st overall in both points and assists. In 245 career QMJHL games with Chicoutimi, Quebec and the Rouyn-Noranda Huskies, Bibeau scored 214 points (84 goals, 130 assists). He added 29 points (15 goals, 20 assists) in 40 QMJHL Playoff games, including 29 points (14 goals, 15 assists) in 2019 as Rouyn-Noranda won the QMJHL Championship. The Huskies went on to capture the 2019 Memorial Cup, where Bibeau scored a tournament-high five goals and was named to the Memorial Cup All-Star Team.