The legal age for consent in NY is 17 so the 19 year old would violate the law if they had sex.
I am a former federal and State prosecutor and now handle criminal defense and personal injury/civil rights cases. Feel free to check out my web site and contact me at (212) 385-8015 or via email at Eric@RothsteinLawNY.com. The above answer is for informational purposes only and not meant as legal advice.
My advice to you - as a mother - would be to wait until you are older. Otherwise, there's nothing to look forward to!
Under the law, a person (in your case - your boyfriend) could be charged with Rape in the Third Degree (which is "statutory rape") if he engages in sexual intercourse with someone incapable of consent for reasons other than being under the age of seventeen; or if he is 21 or older and the other person is less than 17; or if he has sexual intercourse with another person without consent where the lack of consent is by reason of a factor other than the incapacity to consent.
So technically, he could not be charged with a crime if the sex is consensual. But, my best advice is to wait until you are at least 17.
I have been practicing criminal law for over 20 years and am happy to help you understand the law, but my comments here are not to be taken as legal advice.