Protas, 18, was ranked 16th among centers and 30th overall among North American forwards by NHL Central Scouting. Teammates with Brett Leason, who the Capitals selected in the second round (56th overall) in the 2019 NHL Draft, on Prince Albert, Protas registered 40 points (11g, 29a) in 61 games last season. The 6'5", 205-pound center ranked seventh among WHL rookies in points and led all WHL rookies in playoff points with 22 (12g, 10a) in 23 games.
The Vitebsk, Belarus, native represented Belarus at the 2018 Under-18 World Championship, recording four points (1g, 3a) in four games, and also earned a silver medal at the 2019 Division 1 - Group A World Junior Championship, recording five points (2g, 3a) in five games. Protas became the first Capitals draft pick from Belarus.
The Capitals acquired the 91st overall selection in the 2019 NHL Draft by trading their 118th and 129th overall selection in the 2019 NHL Draft to New Jersey.