There are many good websites to visit in preparation for your FCC license exam. Here are just a few: Hamstudy.org, The American Radio Relay League (ARRL), eHam.net and others. Many of our recently licensed hams used hamstudy.org. The American Radio Relay League sells study guides that have helped thousands of people get their license. There is a separate license guide for each license class and they are available through the ARRL or on Amazon.com. The question pool for all license classes changes regularly to ensure integrity of the licensing process. Make sure the study materials you use are current. You can refer to the ARRL question pool information page to ensure the materials and/or question pools you study are correct for the date you plan to take the exam.
There are many YouTube channels available to assist you with the process. Most people use YouTube content in addition to a paper based or on-line study method. But, we all learn differently so find a method that works best for you and stick with it. You can always check your progress by taking a practice exam on eHam.net.