It is believed that a pupil will have a competitive advantage (both when entering university and in their future career) in an area in which the pupil (rather than the parents) has both a genuine deep interest and good abilities. While studying at school it is possible to focus on the pupil’s interest in subjects close to a possible future profession and on the comments of teachers about the pupil’s abilities and achievements in these subjects. In the absence of any certainty in the choice of subjects, you can go to the websites of several universities and look at different existing courses, discarding those that are not interesting at all and narrowing down the list to those that may be potentially interesting.