In order to become a HAM, you need to get a license by passing the HAM Exam. This exam covers a wide variety of radio topics. Before your exam, you need to read the exam book, which you can find here. In order to get a HAM License, you need to find a local VE (Volunteer Examiner) to administer the exam. It is often easiest to find an exam by asking your local club. You can also find exam sessions using the ARRL’s tool:
There are three levels of HAM Radio Licenses, each with a different level of privileges. Each one has a different test, that you need to pass. The three levels are Technician, General and Extra. If you look on the band plan, you can see the different frequency each class is allowed to use.