A Mossberg Model 380, .22 caliber, semi auto rifle with an unmarked, 4 power scope sporting a 3/4" tube. I was eleven and got it for Christmas. I remember that when it was revealed, from behind a chair in the living room, it took my breath away.
It was an "okay" shooter but, came with no instructions for the rifle or the scope. My dad had no idea how to adjust the scope and had never shot with one. I suggested removing the elevation and windage covers although at that time, I had no clue what they were either. My dad didn't think that would be a good idea.
I soon learned from a friend how to adjust the scope and zero the rifle. I shot a lot of the "yellow" box Winchester .22 Super X ammo and while it jammed some, if I kept it heavily lubed, it functioned pretty good. I traded it many years ago and upgraded to a Browning lever action .22 rifle but, it didn't last that long either.
The first shotgun was a Savage 311D, 12 gauge. The first handgun was a Ruger Single Six Convertible.
I was fortunate to grow up with a dad who was, except for scopes, knowledgeable of firearms and who had a modest collection. I still have all of his but, my "first" firearms were traded for upgrades later in life.