The 20-year-old said that he is "excited" to be getting a chance at Meadow Lane, and hopes that he can catch the eye of Bhoys boss Neil Lennon with some impressive performances.
"It's a great feeling, I'm really excited to come and play here," he told Magpie Player.
"I want to go and show that I can play at a good standard, League One is a great league and hopefully the manager will be watching back home.
"I hope that I can impress and get my name known down here as well. I'm confident that I can come here and make an impact."
McGregor, who becomes Chris Kiwomya's eighth summer signing, scored for the Magpies in a pre-season game against Brentford.