Under Florida Law, it is illegal for a person over the age of 16 to have sexual contact with someone under the age of 16. Consent will not protect your boyfriend because a person under the age of 16 cannot legally consent.
Be aware that there are different definitions under Florida law which qualify certain acts to be illegal, including, but not limited to sexual intercourse. If you and your boyfriend are dating, but are not having sexual contact of any kind, then he should not have any problems. The law does not prohibit you and he dating, it prohibits you and him having sexual contact of any kind.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.
No, your boyfriend will not go to jail for dating you.
In Florida, a sexual relationship between an 18-year-old and a 15-year-old is stautory rape and could result in the adult being charged with a very serious felony.
The question is, if law enforcement finds out, would it decide to prosecute? One cannot say. Typically, (1) the younger the child and (2) the more years between the child and the adult increase the odds of prosecution.
However, sometimes even when the adult is only 18 or 19 and the child is only 2 or 3 years younger, the adult is prosecuted. Such is known as a "statement" case.
I am not condoning sexual relationships between those aged 18 and 15, but if a male and a female those ages were to get married and then have sex, there would be no chance of prosecution in Florida.
There are many, many people in jail right now who are still presumed innocent of their charges while they wait for their trial. So, even if he hasn't done anything illegal, it is not to say that if a complaint (probable cause) leads to his arrest that he won't "go to jail."
It is legal, though not recommended, for an eighteen year old to date a 15 year old. With that said, it is 100% illegal for you to have any sexual contact other than kissing (and even then some prosecutors will try to prosecute you). My advice is to date someone your own age.