The most amount of pieces [ever] per set
The largest LEGO set by piece count is :
31203: World Map (2021)
Piece count : 11695
Second:
10276-1: Colosseum (2020)
Piece count : 9035
Followed by :
75192-1: Millennium Falcon (2017)
Piece count: 7541

Largest Techic set :
42100-1: Liebherr R 9800 (2019)
Piece count : 4108
Second :
42082-1: Rough Terrain Crane (2018)
Piece count : 4057