Protas previously played two seasons of major junior for the Prince Albert Raiders of the Western Hockey League (WHL), and was selected 91st overall by the Washington Capitals in the 2019 NHL Entry Draft.

Heading into the 2019 NHL Entry Draft Protas was the 30th ranked North American skater, and was selected 91st overall by the Washington Capitals.

[2] He played for Prince Albert in 2019–20 season, which was ended prematurely due to COVID-19; in 58 games he had 80 points, which placed him ninth in the WHL in scoring and the highest European player.

[4] With Minsk's season over, Protas was re-assigned to the Hershey Bears, the Capitals' American Hockey League affiliate.

[7] On 19 January 2024, Protas signed a five-year contract extension with the Capitals, carrying an average annual value of $3.375 million through the 2028–29 season.