The requirements may vary depending on the country. Generally, an applicant needs to have graduated from high school and have a bachelor's degree, and be able to pass the entrance exams for law school at a University. And then there is a 3 course of study to obtain a law degree. Being called to "the Bar " means that a person is now a fully qualified lawyer, able to practice law in their jurisdiction.
A bachelor's degree, then go to law school for about 3 years (if you attend full-time)..then pass the bar.
You need a law degree in most states and then you need a license to practice law. The only 'training' in most places is what you get on the job.