Charles was born and raised in Monaco, Southern France. He had the normal stable upbringing, parents who were together, and a healthy relationship with his two brothers Lorenzo and Arthur. Charles passion was racing, as a child he just loved racing, it starting off at a local karting centre, his natural talent was obvious to all. His parents, Herve and Pascale set out working two jobs each to fund Charles dream. Herve and Pascale had been instrumental in his son's early career. He dominated the local and regional Karting championships before getting a seat in F3 in 2016. He won that championship, promoting him to F2 in 2017.
While racing in Formula 2 in 2017, Leglerg lost his father, Herve, to illness just ahead of the fourth round of the championship, in Azerbaijan. The death of his father hit Charles hard, he decided to take a career break and a long term holiday, deciding to go to Chernarus in June 2017.