You live in the UK. Average life expectancy is about 77 I think? So you're extremely likely to live to at least 40 or 50, even if you smoke and drink and take drugs and all the rest of it.
There's plenty of time for being remember as any of those things, or all those things, or something you don't even expect you'll end up doing.
I thought the same thing as you when I was your age. It's not really a fear - it's an excitement about life ahead, and a frustration that life doesn't seem to be happening RIGHT NOW. But actually life is happening to you right now too.
I also thought there was something wrong with me - everyone does. Guess what - there is something wrong with everyone, nobody's perfect! That's what makes people interesting