Krishni
The questions you listed here are very interesting. Many of them are 'demographic' questions e.g. age, what subject studying, and so on. Those will help you produce a 'table of interviewee characteristics' for your research paper.
The questions I find most interesting are the QUALITATIVE questions such as 'Why do you drink alcohol?'. There are actually a lot more closed questions in this list than open questions, so I suspect you are probably naturally a 'quantitative' researcher who would really like to design a survey which students could complete by filling in boxes, and not much free text. This type of research is very useful for answering quantitative questions such as 'what proportion of students drink to excess?' or 'do the science students drink more than the arts students?'.
But the WHY questions are best answered, at least initially, by open-ended interviews in which you ask a question and record the person's (longish) response.
Maybe think about some more 'why' and 'how' questions?
