I am an ESL teacher from Europe. I would like to become a teacher in New York City. Do I have to have my registration at New York City Department of Education to get a job?

for a private school you may not need to be licensed with the city...although it wouldn't hurt...you will need a state license or equivalent thereof that says you are certified to teach ESL...private schools do not always follow the same rules as the board of education, but do adhere to the state requirements...you need to look at the schools individually and ask about their hiring procedures...