First you need to start with psychology. Make that your major. Then get more specific from there. Some colleges offer concentrations in certain fields. For instance, from personal experience, I’m a math major. My concentration is applied math. All the other math majors and I, regardless of our concentration, will graduate with a math degree even though we followed different concentrations. Still, graduate schools and employers can see what your concentration was in college. So see if your school has a concentration leaning in the direction you’d like. If you’re not sure which one is for you, talk to a professor. If you’re just starting school, then ask your adviser, if you have one. Your school might not have concentrations but a specific major in disorders. This is usually in larger universities though.

You would wish to start with an undergraduate major in psychology, but keep an eye out towards a program in Social Work.