real analysis – Prove that if $f(n+1) > f(n)$ then $forall nin N, nleq f(n)$

The whole problem is “Let F : N → N be a strictly increasing function, that is, for each n ∈ N we have that f(n + 1) > f(n). Prove that
∀n ∈ N we have that n ≤ f(n).”

I have no idea how to start it, particularly how to get to a spot to compare n and f(n). Any help is welcome, thank you!