Most of the time when you buy a camera it comes with a lens similar to this:
I'm an advocate for using manual focus. Why? Auto focus sometimes gets it right. Other times it gets it SO wrong! Example: I was doing a mini-series where I took pictures of people who live here but who don't participate in the same religion as 90% of the residents. I was shooting one person and I accidentally left the camera in auto focus. Instead of focusing on her, the camera focused on the wall behind her. Not cool. Yes, auto focus is easy, leaving the camera set on the little green box is easy, but by doing that you just turned your very expensive camera into a point-and-shoot. The price of the camera means nothing if you don't know how to operate it. That's why you're here right? That's why photographers get mad when you say something like, "Your camera takes really nice pictures." You have to know how to operate it in order for pictures to turn out good.
I want to you to find a person that will be willing to sit in front of your camera while you practice for a few minutes. It doesn't have to be the most beautiful person in the world, but it does need to be someone who can sit still for more than 2 minutes. Probably not kids.
Set them outside. Why outside? Because indoor lighting is horrendous! Take pictures outside whenever you can. The lighting is so much better. You don't have to worry about people looking yellow or anything. Overcast days are nice, but you can always sit them in the shade if it's sunny. Taking a picture under bright sunlight will make them look like this:
While that's a cute look for those girls, most people won't like it. Bright sunlight creates shadows on the face that ages people quickly!
So get in the shade. Make sure your exposure is set correctly when you focus on them. Take care to focus on their eyes. You should see a slight reflection of light in the eye. Once the eyes are focused, everything else will fall into place. Press the shutter. How'd it turn out? The key to photographing people: make sure their eyes are focused!
I hope this has helped you in some way. If you have other questions or need extra explanations on anything, please let me know!!!