For me, there was a difference between the first shotgun I got to use, and the first shotgun that was "mine". A few years difference, in fact.
The first shot gun I got to use was a bolt action, tube magazine .410. The only markings on the gun at all were "2 1/2 & 3 in shells" on the barrel. My Grandfather kept it (ot was his cousin's gun), but he let me use it. After a couple times, and shooting a whole box of shells (a major expense for me at the time), without hitting a single bird, I was disgusted with the .410.
So, in my youthful wisdom, I moved on, to my Grandfather's shotgun, an Ithaca double barrel that he bought new (and made to order for him) in 1909. Now that was (and still is) a fine shotgun! However, it has its ..quirks. the stock was made to his order, and has a bit more drop than is common today, so the gun comes "up" a bit more than you expect when fired.
The first shot I took at a patridge with that gun, I laid my thumb over the wrist of the stock after pushing off the safety. And I was promptly rewarded with a split lip!
I never made that mistake again!
That gun and I spent many hours together, and it never let me down, once I learned to respect it. Grandpa let me borrow the gun, whenever I liked, but I was not allowed to keep it. It became understood that someday, that gun would be mine. But Grandpa, smart old buzzard that he was, made the rule, and while I would have that gun someday, it would only be after I turned 25 years old.
His concern was that, if I got ownership of the gun too young, that I might wind up having to sell it, as young men often do when they run short of money. And his wisdom proved correct, I did wind up having to sell some of the guns I had owned for just that reason. He felt that by the time I was 25, I would be responsible enough (and well off enough) to neither have a need, nor desire to sell that gun. And he was entirely correct.
The old man passed before I was 25 (and I miss him still) the Ithaca stayed at the house for a couple years, until I was of age to keep it myself. Mom & Dad saw to it that his wishes were carried out, and today I clearly see the wisdom of it. I've had that Ithaca for nearly 30 years myself, the only real thing I have of my Grandfather's, and it will never be sold, while I live, no matter what. In time, it will go to my granddaughter (at this point, no grandson, yet), probably, when she is old enough and responsible enough.
Next shotgun I got to use was a store brand 16ga that Dad loaned me. Broken stock with a couple of wood screws through the wrist. Beater gun for a kid to carry hunting rabbits & squirrels during deer season.
The next season, the same, except the gun was a Marshwood double 12ga. 30in tubes. I remember that gun was heavy!
The first shotgun I ever owned myself was my 16th birthday present, a Winchester Model 12. 30in, full choke. Made about 1922. Bought at an auction, for $90 (an other bidder ran the price up, not even knowing what the gun was, beyond 12 ga pump). Still a lot of money for us in those days.
After I paid for the gun and was returning to my seat, the guy asked me what I was. I told him, Winchester model of 1912. He offered me $125! I turned him down!
That gun and I spent many good years afield, and I still have it, 40 years later. That gun and I just "fit". Once shouldered, it just seems to point and track by itself, and misses are few and far between, or were, back when I used it often. I haven't taken it out in some time, but as I write this, I'm getting the urge to spend some more time with my old friend.