Classification of groups of order $p^2q$

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I have done the classification of groups of order $p^2q$, where $p>q$. $p,q$ odd distinct prime

If $P\in Syl_{p}(G)$ & $Q\in Syl_{q}(G)$ then Case $1$: $P=\Bbb Z_{p^2}$. I have done.

But my question is for Case $2$: $P=\Bbb Z_{p}\times \Bbb Z_{p}$ Here $\phi: Q \to Aut(P)$ s.t $q\mapsto \phi(q)$ where $\phi$ is injective. Then as q is odd prime $o(\phi(q))|(p-1)p(p+1)$ [Because we can retrict $\phi$ to $SL_{2}\Bbb (Z_p)$
Now $q \not|p$ So $q | (p-1)(p+1) \Rightarrow q|(p+1)$ or $q|(p-1)$

Now Can anyone help me from here. I am also trying.

Actually 1st problem is finding a Subgroup H $\in$ $SL_{2}\Bbb (Z_p)$ of order $(p+1)$ & $(p-1)$. Then cases for $q$.

  • One more thing before giving this problem. I was observing some related question on this in mathstack. But I couldn't understand many notation & result. Perhaps out of my knowledge. So please don't refer any other answer & give the answer on the basis of Semidirect Product & explain it thoroughly. Thanks in advance.
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Hint

Consider the field $F$ with $p^{2}$ elements, and an element $z \in F$ of order $p^{2}-1$. Now $z$ acts linearly by multiplication on the additive group of $F$, which is isomorphic to $P$. This will yield an automorphism of $P$ of order $p^{2} - 1$.