Should I get a part-time job?

I (22F) am currently a 3rd year college student. My parents are separated, but they are able to provide for our studies even though they don't earn that much. But my mother is mostly the one who provides for us — me and my sister, who's also in college. My sister and I are studying in public school, so we don't have to worry about tuition fees. However, at my age, I have this urge to not depend on my parents financially anymore. I am planning to apply for a part-time job since I only have night class (5:00-9:30 pm). But I am still hesitant about whether I should continue with this plan because I might not be able to focus on my studies if I do this, since I have quite a major subject. And I am afraid that having a part-time job while studying will physically and mentally drain me, since I am also running for Latin honors, which is my ultimate goal.