A boy becomes a bar mitzvah automatically when he turns 13. It doesn't matter where the boy is when he turns 13. If the family chooses to celebrate that occasion, they can do it anywhere they want. Contrary to popular belief, there is no such thing as a "bar mitzvah ceremony".Typically, A bar mitzvah helps lead the Saturday morning prayer service, which involves chanting from the Torah. But this is technically not a bar mitzvah ceremony; it is a Shabbat morning service that the Bar mitzvah takes part in for the first time as an adult (in the eyes of Judaism).Following the service, there may be a party which can be held almost anywhere.