A shotgun is probably the absolute best first gun a kid can have.

I would suggest a Winchester 1300 black shadow deer combo that will come with a rifled slug barrel and a 28" vent rib barrel. He could literally hunt everything from squirrels to bears with a single gun.

My first gun was a Winchester 1300 I got when I was 11 years old. It has been a flawless workhorse. I still have it 20 years later and it works as good now as it did new.