That player is Ottawa Senators captain Brady Tkachuk, whose brother, Matthew Tkachuk, plays for the Calgary Flames. Brady and the Senators have yet to make the playoffs since he was drafted fourth overall in 2018, so he's been enjoying the 2022 Stanley Cup playoffs cheering on his brother and the Flames.
He was seen drinking a beer in each hand, with two more in his back pockets. Judging by how full he looks in the video below, it appears that he may have finished all four and then some: