it's your life and if you don't want to be at Oxford you really shouldn't go as it is a high pressure environment and you will end up hating it if you're not passionate about being there and studying your course. it is your life, not your parents life! If they really won't take no for an answer then there is also no obligation for you to accept an offer should you get one, people do turn down Oxford for other unis every year. And the process is very competitive, if you're not passionate and your heart isn't in it you might not do as well e.g. at interview and not get an offer anyway. Don't go to Oxford just because your parents like the idea, this is about you and your future, not them.