What birth control

What kind of birth control is the best? I'm 18 years old and want to get on birth control because I am sexually active but i'm not sure which one. I've been looking into the implant (iud) or the pill. Which one do you recommend? How was your experience with it? Did you gain any weight? Was it successful?
Also my parents don't agree with this so they don't know im looking into birth control or even having sex.