If every conjugacy class of $C$ is even, then every finite-dimensional representation $V$ of $G$ over $F$ satisfies $V\simeq V^*$

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Let $G$ be a finite group and $F$ a field with $\text{char}(F) \nmid \# G .$ We say that a conjugacy class $C$ of $G$ is even if $g \in C$ implies $g^{-1} \in C$.

Show that if every conjugacy class of $C$ is even, then every finite-dimensional representation $V$ of $G$ over $F$ satisfies $V\simeq V^*$.

Could you please help me with the above problem?

Now assume that $F$ splits $G$. Show that the number of even conjugacy classes of $G$ equals the number of isomorphism classes of irreducible representations $V$ of $G$ over $F$ satisfying $V \simeq V^*$.

We have "the number of conjugacy classes of $G$ equals the number of isomorphism classes of irreducible representations $V$ of $G$ over $F$". Is the second conclusion trivial?

By the way, why it requires "$F$ splits $G$"?

Thanks.