Given a finite group $G$, $|G|=p^am$, $P,Q\in\operatorname{Syl}_p(G)$, then we know that $Q=P^x$ for some $x\in G$.
Thus every element of $Q$ is the image of an element of $P$ under the isomorphism given by the conjugate $\psi:P\rightarrow Q$, $g\mapsto g^x$.
Hence $P$ and $Q$ (i.e. two arbitrary $p-$Sylow) have the same number of element of the same order.
Is this correct?
Thank you all!