Thinking of studying history in the US ?

Hi

I really want to study history at USA university. I’ve secured places in the UK but am taking a gap year now and was thinking of studying abroad, specifically the US.

I’ve heard that universities in the US require everybody to study general classes for a year or so instead of specialising straight away. I was wondering if somebody could develop this and tell me more… I’ve done the IB so would I be doing every subject again e.g. English, Maths, Science..? How long for? Would it be impossible to just focus on history straight away?

If it’s relevant, I’m thinking of applying to Brown, Yale, Rice and Dartmouth.

Thank you!