This is why I feel so uncertain about almost everything. How can one go through life confident about anything if they must not only research everything for them

This is why I feel so uncertain about almost everything. How can one go through life confident about anything if they must not only research everything for themselves, but also overcome their own biases? What makes somebody qualified to evaluate or research anyway? I feel like after over two decades of living, I don't know a damn thing, and I don't mean that in a "I'm so young and naive" sense either.