Monica, Many people would say that a SA XD Mod.2 in any caliber would be a good start. Whatever firearm you get train with it. Know how it functions. The manual of arms. How to clean and maintain. Start with whatever you want and grow from there. Practice, practice, practice. Dry fire. Get to the range. Learn about the shooting sports.

its a little big for a 1st gun and 45 acp is a little harder for a beginner than 9mm. also 45 ammo is about twice the price of 9mm and as a beginner you need to shoot as much as you can. I suggest that you go to a local range that rents guns and try out as many guns as possible before buying one. After shoot a few guns you will have a better understanding of what fit and works best for you

Monica, it is a full size pistol and likely a tad too big. I have no doubt that you could learn to shoot it well but, it is kinda big. Cheers and stay safe.