Is Billy Joel hispanic

Billy Joel is of 100% Jewish ancestry, so no.

From Wikipedia:

Joel was born in The Bronx, New York and raised in the Levittown section of Hicksville, New York. His father, Howard (born Helmuth), was born in Germany as the son of German-Jewish merchant and manufacturer Karl Amson Joel who after the advent of the Nazi regime emigrated to Switzerland and later to the United States. Billy Joel's mother, Rosalind Nyman, was born in England to a Jewish family (Philip and Rebecca Nyman).

He is not of German,French, English, or whatever other descent someone else claimed.