Struggle. No one likes it, but meaning comes from pain. The story that goes "iunno, I was kinda lost so I started volunteering because some guy on an internet forum said it was a good idea" isn't compelling. You need a compelling narrative to generate the meaning you're seeking, and that is only possible in hindsight.

Don't focus on you, focus on the world. Go heads down and focus on making life better for others. Lose yourself in that, and when you look up you will have become your answer.