Yes, you need to learn a lot about electronics, radio and FCC regulations. You also need to pass a licensing exam.
But these are two different things. You didn't learn to drive by passing the license test. You learned by driving, ideally with the guidance of someone who knew more than you do. Same with amateur radio. The sit-down test preparation supplements the hands-on, real-world, experiential learning, not the other way around.
The ham licensing test, in common with those for drivers, airline pilots, ship captains and others, is a mostly a test of your multiple-choice skills, less of a test of your expertise in the subject matter. Therefore, consider studying in a way that helps you distinguish between right and wrong answers rather than worrying whether test prep really prepares you to go on the air. It does, some. But the goal of test prep is a license, not an education.
The ARRL book is a good way to learn stuff and is a reference you'll want to always have in your shack. But to pass the exams, the Gordon West Q&A books are the better way, or at least they were for me.