Well if I remember being 16 correctly it sucks for this very reason. Kids think they are grown up enough to make their own decisions, date people their parents hate, smoke weed, drink and be out til the wee hours of the morning...but really they don't have much life experience or understanding of the world.
Parents still hold the purse strings, have to drive you places and collect you in the middle of the night and are the ones you run to when things go crashing down around your ears..oh plus you still 'live under their roof'.
Your parents are protective because they don't want to see you emotionally or physically getting hurt. Even if it drives you mad, they are well meaning and you'll regret all the yelling at them and fighting that comes with being a 16 yr old girl.
My first bit of advice is to start saving now to take driving lessons once you turn 17. Once you have passed your driving test then the world changes quite a lot. Your parents will allow you more freedom simply because it's so much bloody easier when they don't have to be involved in every outing. As long as you are never stupid enough to drink and drive & you show responsibility to your parents by practising driving a lot & then being super careful after passing the test then driving opens up a whole new world to you.
As for your parents believing your friends are a bad influence. Be adult about it and take responsibility for your actions and explain that you are chosing to do these things, don't let it be blamed on your friends. At the moment your parents are working off guesswork and snatches of information and let me tell you parents often imagine things being worse than they are simply due to lack of information. Let your parents get to know your friends & their likeable qualities.
You are still a child so they are perfectly within their rights to tell you they don't want you smoking dope or drinking. Rather than raging at them and telling them 'everyone else does it' (I'm not saying you do this, just going off my experiences of being a 16 yr old girl!) why not explain the reasons that you believe you should be able to drink, show them that you will be responsible with it and not rolling around drunk and getting taken advantage of. If they still don't want you drinking ask them to give you the reasons for it. If nothing else it will give you a better understanding of where they are coming from & maybe a little empathy with them.
To be fair with the boyfriend issue your parents may well know better than you and see all the pitfalls whilst you only see the world through rose tinted glasses. However the process of growing up is learning new experiences and new things, good and bad. Again the whole boyfriend issue is about showing your parents that you are being sensible and mature (yes that word again) about chosing your man & conducting a relationship. Definitely listen to the advice someone else gave and introduce your boyfriend to your parents. Sure it may be intimidating but I'd imagine your parents are reasonable enough to at least give him a chance. It goes back to what I said about parents imagining the worst. Give them no information and their minds run wild imagining things. When you stop acting in a sectretive manner they stop being so suspicious!