This probably won’t be as confusing as ISO, you’ll be glad to know. 
Composing a photo is just one way you can let your creativity flow. It’s what makes a photo uniquely beautiful. 50 people could take the same photo and not have the same compensation.
I see a lot of people get in the habit of standing in front of their subject, snapping the shot, and leaving it at that. It might be quick, but you don’t get a great shot! Next time, when taking a photo, get different angles and place the subject differently in your photos.You might sit down and take it, get up higher, or stand to the side of your subject(s).
When shooting people, don’t always have them looking and smiling at the camera; catch them doing something else. Catch the little moments you’ll want to remember- not necessarily the smile. Also, when taking photos of little ones and babies, remember to get down on their level.