Birth control (( HELP! ))

Im 15 and im sexually active with my boyfriend and we are not TTC and my parents know that me and him have messed around and i want to be put on birth control but i dont know how to tell them, i feel like it would help with my cramps and also prevent any unplanned pregnancy. i dont know how to bring up the topic with them or even start the conversation let alone tell them. i dont want to make the same mistakes my parents did and have a kid as a teen and be forced to struggle to make ends meet. i want to give my future kid everything they could ever want without having to give an arm and a leg for it. any tips?