Oxbridge interview for maths

Assuming you're talking about Oxford vs Cambridge Maths undergraduate interviews. I'd say generally they're fairly similar. Oxford tends to interview significantly fewer candidates as they already have MAT to narrow the selection pool down. It's also harder to get an offer from Oxford as Cambridge can narrow down more with STEP. Thus it could be argued that Cambridge interviews aren't the 'final hurdle' - whether that makes things easier for you or more difficult is a matter of personal preference.
There are differences between individual colleges in both universities in terms of format so take the interview experience of any one candidate with a pinch of salt. Interviews may have also changed format with and since COVID, with some Cambridge colleges interviewing entirely online, some entirely in-person and some online only for international students. I'm not sure of this year's interview format for Oxford.
My advice would be that unless you are really convinced by indisputable evidence that interviewing for one university would suit you much better than the other, I wouldn't use interview style to narrow it down too much. There are many other, more pertinent differences between the two, both in admissions (STEP vs MAT especially) and in the university experience, like the city and course structure.

Hi, thanks for the detailed reply🙂. What do they normally ask and do they ask you to do questions during the interview??