While the classic game Pong is a simple arcade-style table tennis simulation game originally, it can be adapted into a drinking game.
In a traditional Pong game, two players control paddles to hit a ball back and forth, and the goal is to make the ball go past the opponent's paddle. When adapted as a drinking game, rules can be set such that when a player misses the ball and it goes out of bounds on their side, they have to take a drink. Or other specific events during the game, like hitting the ball a certain number of times in a row or achieving a particular score, can trigger a player to take a drink.
So, in its original form, Pong is not a drinking game, but it has been modified and used in that context by people looking to add an element of fun and social interaction with alcohol involved.