If you are new to guns, before you buy go to a range that rents guns, and/or go with a friend that has guns, and try out as many makes, models, and types as you can. Get some instruction on how to shoot both automatics and revolvers. Listen to what more experienced shooters have to say, but remember that anyone who has been around shooting for any length of time has developed their own set of TRUE BELIEFS, and what works for them may not work for you.
My suggestion to anyone starting out in shooting is that their first gun should be a good .22, for the reason that the most important thing for any beginner is practice, practice, practice. Hundreds, if not thousands, of rounds. A .22 will let to afford the amount of ammo you need to get proficient, and if you get a good .22, such as a Ruger Mk I, II, or III, or a Ruger Single Six (two of my recommendations for beginners) it will still be fun to shoot after you have gone on to bigger calibers.