Calling it “finger gun” or “gun finger” does not change the reality. It is a simulation, and not a very good one, of a gun. Generally the kid makes a sound that everyone understands is a simulation of the real sound of a gun.
If the world had been totally insane when I was a kid, as it is now, I would have been jailed for my games of “cops and robbers” “and cowboys and native Americans.” (It actually had another name; you know what it is.)
And the kid didn’t use his fingers to “shoot at another student.”
We seem to be living in a simulated reality. Fingers are treated like real guns and shot-like sounds are taken as real. People declare themselves to be the sex they are not, and everyone around them immediately denies reality and agrees.
I played those same games all the time.
When we were kids in the 1960s, we were always re-fighting WWII with toy guns. The younger brothers (I was one) were forced to be the Nazis, except one kid of German extraction, who wanted to be on the opposition. He would yell out “Dummkopf” and “Schweinhund” while we were fighting, and I recall he had a schwastika painted on his tree house. Wonder where he is today?