Photoshop isn't all that hard actually. You just have to learn how to use it. People mostly use photoshop as a photo editor. Meaning, they just add or remove art to an image to make it appealing. Most common ways of doing this is by using a render as a main focus point of the image and adding onto it, depending on the image via lights, shadows, colors, and actions. If you follow those, an accomplished artwork is made.