<p>You choose a course at Cambridge and you study that. If that is a combined course, such as Social and Political sciences, fine. If not, no can do.</p>
<p>The full course list is here.
[Undergraduate</a> Courses](<a href=“Study at Cambridge | University of Cambridge”>Study at Cambridge | University of Cambridge)</p>
<p>If the combination you want is not on this list, you can’t do it.
Oxford and Cambridge are the least flexible. Other universities may be more flexible, but in general you sign up to study a set course in the UK and cannot easily change it.</p>