Law & age of consent CALIFORNIA

So I have been friends with this guy for over a year now and him and I started talking recently about being more than friends. I am 16 years old, going on my 17th birthday on December 31st. He is turning 18 years old on Tuesday (June 16th) 

I have read that if the minor is less than 2 years younger than the adult, it is not considered felony. Him and I have always been really close and if we were to date it would be a very healthy relationship that I think would last a long time so just to prepare myself before telling my parents and friends etc... We are giving it time so is it illegal if him and I date after he turns 18? Obviously we wouldn't have sex right away but at some point you know....and when that happens I wanna make sure he won't get in trouble because I wouldn't want him to have a marked permanent record because him and I were dating. 

His is confusing but thanks to everyone who read this and tried to help. Please no judgments, I just need advice and help if anyone knows or have ever looked up or heard about the laws.

Thank you,