Advice needed pleaseee

I'm considering have sex with this guy, which over the past couple years I've been on and off with in the "talking stage" and flirted amendously with, but I'm not 100% sure that I should. He sort of has a loud mouth and I'm scared that he'll tell someone and then it'll be heard throughout the school. I don't want people to know my business. I want us to be a low key thing, but I'm unsure of what his actions will be like after sex. Since he is a virgin and I'm not. Maybe I should start off slowly with oral? Please give me advice