Mbabu is currently being played at fullback for the club's U21s.
"To play here in front of the fans and to show how I can play and show what I can do is good," Mbabu told nufc.co.uk. "It's very different. It's bigger, there is more space and you have to run more - that's why I came off, because I was tired.
"I'm very happy to play for this Club and I want to continue to play here."