I have a green card want to get my citizenship an I have my son back in Trinidad i want him to be a citizen too

You may become a citizen through naturalization. You may seek naturalization after being a lawful ermabebt resident for five years (three years if married to a United States citizen). Your son would need to first come to the United States as lawful permanent resident before he could become a citizen. You can read more about naturalization at http://myattorneyusa.com/citizenship-and-naturalization.