By the way, that guy was a random person, literally
Is it possible to get 100% accuracy in a game?

Excellent question
Seems it is possible. I made a quick search here on chess.com and look what I found: https://www.chess.com/article/view/5-perfect-chess-games Hope it helps!

https://www.chess.com/analysis/game/daily/244706904?tab=review
White's speed won them the game, but both scored 100.

https://www.chess.com/analysis/game/daily/244706904?tab=review
White's speed won them the game, but both scored 100.
What format was this, 1-second bullet or what?
Yes. Play all book moves and the last move your opponent makes has to be an out of the book move, hanging mate in 1. Which you should take advantage of and checkmate him.
That will give you 100% accuracy on this site.
Yes. Play all book moves and the last move your opponent makes has to be an out of the book move, hanging mate in 1. Which you should take advantage of and checkmate him.
That will give you 100% accuracy on this site.
Yes. Short game, all book moves, then he blundered.

It is.. I have some myself. Just a sequence of opening moves with a trap in it. it's nothing special
10 move game with 100% accuracy: https://www.chess.com/game/live/108928253076
He lost by resignation right before I took his queen.
I had a game with 100% accuracy in my old account (Its closed). I was playing as white. My opponent, for some reason, played the fool's mate. If u don't miss it, you have 100% ACCURACY!!!!!