Complex sentence: While she did not have ambitions to become a performer early in life--dreaming instead of becoming a flight attendant--she was discovered at age 12, while visiting a friend, by Masayuki Makino, the owner of Okinawa Actors School, a performing arts school.
Split into simpler sentences: While she did not have ambitions to become a performer early in life--dreaming instead of becoming a flight attendant--she was discovered at age 12, while visiting a friend. Amuro was scouted by Masayuki Makino, the owner of Okinawa Actors School, a performing arts school.