I am learning to be realistic with PS now. From my point of view these days, PS has several key points: channel, mask, path and constituency. You can search related posts, and the great gods are very detailed.
At first, I came into contact with AI. Later, I found that PS was much better than AI, so I began to learn PS again. I haven't studied it systematically. My teacher is just an online tutorial and post. I don't know. Have you been to TutsPlus? A foreign website has a lot of tutorials about PS, almost everything, whether it's font making or retouching. If you can read English well, I suggest you go up and study. If you really don't understand it, go to such excellent websites as "Station Cool" or "Youjian" in our country, visit them every day and do more with the tutorial. Within two months, you will find yourself making rapid progress and even making beautiful posters independently.
You don't need to know all the uses of PS. You don't develop software from Adobe. Why do you know so much?
I don't have any books to recommend to you because I haven't read them. It's not that books are useless, but that I can learn from online materials, which may not be as organized as books, but at least the N works on my USB flash drive can show that I already know this person.
I hope it can help you improve.