Getting a degree in legal studies is a long and complicated process. It is also extremely competitive, because due to the high salaries earned by many lawyers, many students compete for places in the best law schools.
Your first step is getting good grades in high school, especially in English and history.
When you apply to university, you should consider one that offers a pre-law degree. You will need to spend 4-years getting a BA degree. Good skills in writing, oral communication, and logic (respectively taught in English, Communication, and Philosophy) are essential.
In your final year of a BA program, you take the LSAT test and apply to law schools. You need to complete your BA to be admitted.
In law school, you study for three years, both general legal principles, and specific case studies in various types of law.
The purpose of law school is that you need to get a degree in law to become a lawyer.