I can share some of my teenage-concerns, current and former, which advice may (or may not?) be appropriate for.

• How to decide what to do with my life, if even possible. What makes me happy? What is important to me? Maybe I do not need to attend college to satisfy my interests? What happens if my model for my future is different from my parents' model of my future?
• How to cope with being stuck in high-school, with a limited degree of freedom and mobility, a lack of tolerance for worthless tasks like chores, a largely immature crowd of peers surrounding me, and no IRL friends who are also rationalists
• Existential depression: feeling overtly depressed over the realization that life is meaningless, short, etc
• Not actually understanding where I fit in intellectually due to conflicting judgments (school performance vs. personal thinking, learning, and interaction)

Most often, the advice I get is to wait for college. The concerns get dismissed because they're juvenile and temporary in nature. However, I choose to assert the importance of the present.