The Portuguese midfielder - who left Sports Lisbon in a £55 million January switch - has revealed he always wanted to play for the Red Devils, and he was overjoyed when the opportunity arose.
Speaking to Mario Djurovski on Instagram Live, he said: "You know, I will say the truth that I was scared. It was a dream [come true] but it was a big dream.
"For me, playing in England and for Manchester [United] was the highest part of my career. To play in the Premier League, for one of the best teams in the world.
"When I received the call saying, 'Bruno, you have the chance of moving to Manchester' I called my wife, my brother, my sister, my mother and just started crying.
"But I was crying through happiness. I fought all my life for this, for this top club. The chance was here and I needed to take it with both hands, to follow my dream.
"My family knew since the beginning that I wanted to be a footballer, they knew my big dream was to be in the Premier League and to play for Manchester."
Fernandes wants to emulate United legend Cristiano Ronald, and he previously revealed the role the Juventus star played in his transfer.
He explained: "I talked about Manchester United with Cristiano. He just said good things about United.
"He said he started living his dream here and he started being a really good player here.
"I think he is happy with my transfer and I also talked with Ole and he said he asked Cristiano about me and he said good things about me which is good.