Gotta Have a 22 !
Why? Why not?
A good answer is that you can do a lot with a 22, mind you not in any defensive capability but for sporting purposes, absolutely!
First, lets make sure we are all talking about the same thing, I'm referring to 22LR caliber pistols and rifles.
These guns have practically no recoil and you can enjoy shooting inexpensive ammunition all day long. Those 2 reasons alone should spark your interest.
Practically speaking you can "ease" into bigger caliber guns by first shooting these 22s first until you feel ready. This also makes it ideal for teaching youth (12+ for rifles, 14+ for handguns) before they "grow" into larger more powerful calibers - in fact many Clubs have youth programs utilizing these very guns, and so too the Boy Scouts.
Furthermore, these guns are typically more reasonably priced which makes them very attractive as first guns to learn and practice.
These small calibers guns are also great for hunting small game if you're into that sort of stuff.
You can also join and engage in "Sporter Rifle" or "22 Bullseye" competitions at Gun Clubs using either 22 rifles or handguns.
There are many models to choose from with some manufacturers having created unique 22 styled handguns and rifles such as the Browning BuckMark, Ruger Mark IV, Beretta U22 Neos etc. and some more traditional gun models that are simply chambered in this ever so popular caliber like a Model 1911, Glock, and plenty of single action revolvers as well.
Feel free to explore and have fun - SAFELY and LEGALLY.
See you at the range...