You can go to law school after you graduate from any college. I’m positive lots of NYU students go to law school every year. NYU has a [pre-law professional advising program](Prelaw), as do many top colleges. There’s no specific curriculum you have to take to go to law school, but many schools have a recommended set of coursework.
You can intern in anything in history; you don’t have to go to a history-related one. You could do a [legal analyst intern position at a financial services firm](http://www.goldmansachs.com/careers/why-goldman-sachs/our-divisions/legal/positions/interns.html), [a legal internship in the U.S. Office of the Inspector General](https://www.oig.dot.gov/about-oig/volunteer-undergraduate-and-law-student-internship-programs), or an internship with the [Department of State](International Narcotics and Law Enforcement (INL) - Careers). You could do a corporate internship with an investment bank or a management consulting firm; students of all majors do those, although they tend to go to students from target schools (NYU is one). You could intern for a smaller or local company. The possibilities are endless - students from all kinds of majors do all kinds of internships, as long as they have the skills and abilities the internship wants them to have.
I will say, though, that the market for lawyers is terrible right now. Most lawyers don’t make the salary required to repay their six-figure law school debt.