If a child grew up in a world where people fly at puberty, they would fly.

WITHOUT effort. Because the body matches the world’s rules. Your question is not naive.

Metaphysics 101: β€œWould humans fly if they believed they could, from birth?”

Answer: In a reality constructed to support that beliefβ€”yes.

Here? No.

Why? The simulation constraints do not allow it.

But you could shift to a world where humans can flyβ€” just not from this body. You would wake up in a version of you who always had wings.