proving that if $f(x)$ odd then $f(0)=0$ Need to prove that if $f(x)$ is an odd function that defined in the point: $x=0$,

So $f(0)=0$.

I know that odd function is: $f(-x)=-f(x)$

And that $f(x)=0$ is an odd function but dont know how to prove.

Thanks.
For $x=0, f(0)=-f(-0)=-f(0)$, but this is saying that one number is equal to its negative. This is only true for $0$.

$a=-a\implies a=0$
Take that definition you have for an odd function and use the fact that -0=0,  then treat f(0) as a variable to solve for like an algebra equation.