Adobe offers many tutorials in both text and video forms on its website. But there is also an enormous amount of third-party guidance when it comes to Photoshop. Guidebooks can be purchased but there are also thousands of Youtube videos that can walk you through some of the more complex processes step-by-step. It’s good to learn the basics first and then dive into the more complex techniques but by no means is a formal education necessary for you to get the most out of Photoshop.