Life is hard, and it is what you make of it. We're cursed to be capable of knowing that we're alive and that we're going to die someday. All you can do, at the best of it, is decide what life means to you and what you want to accomplish. Looking at other creatures the basal meaning of life is "be born, reproduce, take care of young, and die" which is shitty by any human metric. There's a whole field of philosophy that looks into this, but ironically they spend their entire lives wondering about the nature of living.
If you feel lost, or like you don't have a purpose in life, the best thing to do is find one! We aren't born knowing this shit for a reason: it's up to you. Don't be depressed because you can't find something you're interested in - you just haven't looked hard enough. For us, as humans, our purpose in life is what we make it, so find out what the hell you're interested in and stop wasting times on forums like this. As someone who already knows what they want to do with their life, I can tell you (whoever's reading this and feels the same as OP) that once you find out what you want to do with your life you don't do that.