What do you mean when you say we need a purpose?
We are biologically designed to reproduce. So our current purpose is to survive until we're grown to sexual maturity, reproduce, then raise our offspring to a stage where they're able to survive on their own. Then, we either do it again, if we're still young enough, or die and make room for the next generation. That seems like a very depressing purpose to me, but this is how evolution works.
I think that we now have the intellectual capacity to transcendent this cycle. We've been for a while, and we formed societies, developed technology. Our first models were small tribes, very much hippie-like little communities, that suffered from attrition by tribe warfare and rule of the strongest, where reproduction was controlled by "the fittest". Then we developed monarchic systems that provided a much more stable life for everyone, but ran on servitude (slavery) of peasants. We experimented with systems like communism, that then lead to terror by the ruling class (can still see that in China today), and landed on a somewhat democracy-adjacent system of capitalism that we're running today, and that's not sustainable, because we're destroying our planet.
What's next, and what purpose for the individual do you have in mind?