What this anon said but don't just sit there waiting for it to come because it never will. Go and find it, try stuff.
Try things, find stuff you like, develop yourself in those things that you like (only through hard work do we end up with something worth keeping, and we learn to find the joy in that which we do), and let them grow on you as you do them, until one of them becomes your "purpose". You have to decide what's purpose for you, nurture that light and let it become bright enough that it'll guide you through the darkness.
I know exactly how you feel, I feel just like that, right now, these days. But I cope with a goal I set to myself. Even though I'm working reallllly slowly towards it, I'm working, and I keep that goal in sight. Of all the different things I've tried, this one seems worthwhile.
It is also something that, I realized, I can work towards wherever I am: here with my parents, in the city, or in nature travelling. The point here is that I can keep the flame alive despite of external circumstances. It seems like I'm likely to be trapped in a soykafty environment for the foreseeable future, and this one thing is the only invariant that can make my life worth the struggle.
Best of luck OP, don't forget to try, and do your share of effort, nothing comes without effort!