"according to psychosexual development theory, when the erogenous zone centers on the genitals, a person is in the stage."

The person is in the phallic stage. According to the psychoanalytic theory developed by Sigmund Freud, the phallic stage is the 3rd stage of psychosexual development, occurs between three and six years. In this stage children explore their bodies by touching and seeing their genitals and seeing the genitals of others, also learn the difference between male and female, and the dynamics of the relationship with their parents.

I hope my answer can help you.