If you mean all four tournaments (Australian Open, French Open, Wimbledon, U.S. Open) that would be Maureen Connolly in 1953 at the age of 19. Steffi Graf was also 19 when she won the Grand Slam in 1987 but was three months older than Connolly. The youngest woman to win a Grand Slam title was Martina Hingis who won the doubles event at Wimbledon (with Helena Sukova) in 1996 at 15 years 9 months. Hingis is also the youngest woman to win a Grand Slam singles title, winning the 1997 Australian Open at 16 years, 3 months.
Raffel Nadal belongs to Spain is the youngest male to win grand slam .
As of yet, no one male golfer has won the Grand slam. However Tiger Woods is the youngest player to win the career Grand Slam, he did so at 24.
Jelena Ostapenko is the youngest women to win a grand slam at the 2017 French Open.
I think monica seles. Then martina higus. Then maria sharapova.-
that would either be aggasi or sampras
Nadal can win any grand slam.
Na Li of China
as Far as I know; Boris Becker, 17, Wimbledon