If I was starting out as a gun owner and had a .22 rifle as my only gun, and knew what I know now, I would try to follow the excellent advice given by my readers in these comments. I will try to collate that advice, if I make any major blunders, well, comments are open, and I’m good at blundering.
Guns fall into categories. I’m going to call them shotguns, hunting rifles, military rifles, plinking rifles, full sized handguns, CCW handguns, and plinking handguns. Others may draw lines differently, and a gun may fall in more than one category depending on use. This will be a series of posts, and will examine some of the choices in each.
Assuming you are going to buy a gun every three or four months for a couple of years until you have a basic set, there seems to be some agreement on the necessities, if not the precise order of purchase. Here is the first decision point. If you are planning on getting a carry permit, perhaps the second gun should be a carry gun.
The next question is revolver or semi-automatic. Then caliber, then general size. Notice we are not talking about companies or models yet. At this point, it is time to meet some other shooters, visit a range that rents guns, start reading about models. You want to make an informed choice. Sometimes it will come down to how the gun feels in your hand, or how it points. The choices are myriad and you are trying to pick just one.
From the comments, I give the nod to Jay G of Marooned. I agree, starting over, my first handgun would be a quality revolver in .357. He mentions the S&W models, I would add that I think a Ruger GP100 or Security 6 would also be a good choice. They can shoot .38 ammo for practice. They could be carried, although fairly large compared to other options we will explore later. There are lots of ammunition choices, many different bullet weights and types, and good options in quality defensive loads. It will be one you will never sell. You will learn to shoot with it. Sometimes you will wonder just how many rounds have been fired in it. When reloading comes along, it will be the caliber you learn with. As your safe fills up, it will be possible to get a smaller CCW pistol and a lever action carbine in the same caliber. As Midwest Chick observed, managing the number of calibers you buy helps manage your ammunition.
Focus on the journey, not the destination. Joy is found not in finishing an activity but in doing it.