Let’s back up for a minute. You are interested in NYU and Oxford but from your other threads, you can’t afford to pay for AP study materials or summer programs. On CC the first question is always: what can you afford? NYU does have a few great scholarships- but they are very competitive, and for most students are famously stingy with financial aid. Oxford has no meaningful aid for American students, so you need to be able to spend $45K+ / year.
For the UK, you don’t have a major: you have a subject and that is all you study. First year you typically have few (if any) class choices; in the following years your choices are electives within your major subject. So, to get full information about the requirements, look up the subject. For example, the information for prospective undergraduates looking to ‘read’ (study) English is [url=<a href=“http://www.english.ox.ac.uk/prospective-undergraduates.html%5Dhere%5B/url”>http://www.english.ox.ac.uk/prospective-undergraduates.html]here[/url], including details about the course, what they are looking for, and admissions requirements.
As @Conformist1688 says, the Oxford website is very clear. The larger point about Oxford (and the UK in general) is that they provide the information (the websites are amazing), but they expect you to figure things out for yourself. This is true all the way through, so it works best if you are very independent, self-motivated and good at figuring things out.