You can do numerous subjects by studying biology, all across the sciences! One of the benefits from studying science and mathematics is that is gives you a strong foundation for studying a wide range of subjects and careers. You have already mentioned forensic sciences, but you could study medicine, veterinary medicine, health sciences, sports science, biochemistry, pharmacy, pharmacology, etc.
Question for you: what do you enjoy doing? What would you like to study?
I know a lot of people that studied Forensic Science at University because in Edinburgh there is a really good course than you can do and it’s really popular. However a lot of these people realised that they only started to study it because they thought it was cool and glamorous because of programmes like CSI!! You can change your degree at any time. If you are doing forensic science, then your main subjects are chemistry and biology. You could decide to specialise in either of these subjects rather than forensics of you wanted to! And within those subjects you have all kinds of science: stem cells, genetics, biotechnology, diseases, parasites, zoology, physics, biochemistry, drug discovery, renewable energy…
A lot of my friends finished their degrees in Forensics but then couldn’t get jobs because there are not a lot of forensic jobs in the UK. But they all have jobs now. One of them is a teacher in a primary school, one of them is doing a PhD in biochemistry, one of them works for an oil company, one of them works for a company called P&G who make detergents and beauty products and one of them works in drug discovery.
But that’s just from the people I know, just imagine what other opportunities you have!!