Ok I'm new to shooting, and as of today have never shot a gun before in my life. I want to start going to the shooting range here and learn the trade. My dad use to collect guns but passed away before I could learn anything from him.
I always here, start w/ a 9mm, start w/ a .22, start w/ this, start w/ that..... What is the best gun to start off with?
Also, how is the power of a hand gun measured? For example is 9mm the widthe of the bullet, if so what's the size difference between that and a .22? is 22 the MM also? Need some info please.

