You can take better photographs if you learn to separate subject from background. There are many, many ways of doing this. Here are a few rules, and there are exceptions to all of them.
1. Fascinating subject and boring background.
2. Subject is whole and background is cut off.
3. Subject is larger than other similar things in the frame.
4. Simplify the photo so there is nothing to distract from the subject. Getting closer may work.
5. Bright subjects and dark backgrounds. Eyes are drawn to bright areas of a photograph.
6. Subject is in focus while the background is out-of-focus.
7. Subject is a different color and/or texture from the background.
8. Subject has more contrast, more detail than background, which is washed out.
9. Compose the image so the subject is the center of attention by using the Rule of Thirds or Lines to Corners or both.
10. Eyes of people in the frame are looking at the subject, or their arms are pointing, or they are saluting, or they are otherwise paying attention to the subject.
11. One of Many: the subject is one of many in the photo, but has a unique feature. In a group of dark horses, it’s the Appaloosa. In the line of ballerinas, it’s the football player dressed in a tutu.
All of these gets complicated when there are two or more subjects, or the background is as important as the subject.
Photo above: A Walk in Washington, D.C., June 2, 2019.