Growing up in Cicero, New York, Farabee competed with the Syracuse Nationals, Buffalo Jr Sabres, and Selects Hockey Academy at South Kent School.

[5] As a child, Farabee competed with the Syracuse Nationals at the Bell Capital Cup in Ottawa before playing above his year level with the Buffalo Jr Sabres at the Quebec International Pee-Wee Hockey Tournament.

[8] Farabee was chosen to captain the team in his second year by coach Seth Appert as a result of his "competitive, all-around game that belies his size.

[9] Farabee played one season with the Boston University Terriers men's ice hockey team, recording 36 points in 37 games.

[1] He praised his time with the Terriers, saying, "I think my down-low, below-the-goal-line game has gotten a lot better than it was a year ago...As far as protecting the puck and holding onto it and not making plays too fast to where I turn it over.

[10] However, through showing his offensive prowess as team captain in the Development Program and at Boston University, Farabee was selected in the first round, 14th overall, by the Philadelphia Flyers in the 2018 draft on June 23, 2018.

[21] Four days later, Farabee scored his first career NHL goal and assist against the Chicago Blackhawks but both were overturned due to teammate Kevin Hayes being offside.

[28] As the Flyers beat the Lightning, he scored the game-winning goal against the Montreal Canadiens in Game 1 of the Eastern Conference First Round Playoffs.

[29] After playing well following his jump to the first line in the round-robin finale with Jakub Voráček (undisclosed issue) out, Farabee stayed with Claude Giroux and Sean Couturier in Game 1.

[34] Later that month, Farabee scored his first NHL hat trick in a 4–3 overtime win against the Islanders, becoming the second youngest Flyers player to achieve this feat during the regular season.

[40] During the 2024–25 season, his sixth with the Flyers, Farabee was traded along with Morgan Frost to the Calgary Flames in exchange for Andrei Kuzmenko, Jakob Pelletier and two draft picks on January 30, 2025.

[10] He has also drawn comparisons to Brad Marchand and Zach Parise due to his "high motor and a good deal of intensity.

[44] The following year, Farabee competed at the 2018 IIHF World U18 Championships,[45] where he recorded four goals and four assists for eight points in seven games to lead the team to a silver medal.