If you are interested in starting to learn Photoshop, you can find lots of great sites that have tutorials to help you. Look for the most basic concepts, for example how to navigate around the graphical interface and what the tools, buttons, and commands do. Don’t dive into advanced material before you’re ready. It is challenging enough to learn Photoshop as it is - try to master the basics first. Photoshop is easily the best program available for creating graphics you can use.