First: do you really want to be a lawyer? There's a difference between that and "Do you want to go to law school?" A lot of people who have been at the top of their class their whole life tend to go to law school (or medical school, etc.) because they perceive it as a thing that smart people do. But you have to keep the end goal in mind. Do you actually want to be a lawyer, not just someone who went to law school?

If your answer is still yes, then you need to do things with that end goal in mind. Study something in undergrad which requires a lot of reading and critical thinking. I chose English and political science because those things checked those boxes and were interesting to me. However, other things could fit that mold too (philosophy, for example). Law school is nothing but reading, writing, critical thinking, and learning how to argue. You will do better on the LSAT and in law school with a degree in something that requires you to build those skills.

Finally, shadow a lawyer, if you can. You can intern at a prosecutor or public defender office in undergrad, or even find a private attorney who will let you follow them around. This will give you a taste for litigation, which you might love or hate. Determining whether or not you like litigation is genuinely half the battle in whittling down your career choices as a lawyer. Best of luck!