Hello there, as far as I know, most unis do not really care what GCSEs you take, as long as you get good grades in them. This is especially as you don't know yet what field you would like to enter in future. You will be more likely to get a good grade in a subject that you enjoy and are already strong at. So I would recommend picking the subjects that you find interesting and that you think you can get a good grade in. I hope this helps!