The club has been actively seeking top young talent since the start of the year, investing £111 million in new signings this summer.
In an interview with the club's media team, Nypan expressed his happiness and pride in joining Manchester City. He also mentioned his eagerness to learn from the club's coach, Pep Guardiola.
"I am incredibly happy and proud to have joined Manchester City," Nypan said.
"It's a dream come true for any young footballer to be part of this club and to join such a talented group of players," he added.
Nypan also mentioned the connection between Norway and Manchester City, citing the presence of other Norwegian players like Erling Haaland and Oscar Bobb.
"I am very proud to have become the latest Norwegian player to join the club," he said.
