Why it is Important to give a Jewish baby a Hebrew Name

Importance of giving a Jewish baby a Hebrew name in addition to an English name

Certain religious rituals require Hebrew names. Hebrew names are used for calling people to the Torah. Certain prayers, such as the memorial prayer or the prayer for the sick, use the Hebrew name. Legal documents, such as the marriage contract or ketubah, also use the Hebrew name.
Orthodox Jews and Israelis often give their children a Hebrew name, and that name is used for both everyday and religious purposes.
Elsewhere it has become customary for Jewish parents to give their children two names - a secular name for use in the gentile world and a Hebrew name for religious purposes.