Each school is different when it comes to which GCSE subjects must be taken by students and which subjects are optional. Every student has to take a core set of subjects that include Mathematics, English and Science. Typically, optional subjects are chosen from groups such as:
Arts (e.g. Art, Drama, Theatre Studies, Dance), Design and Technology (e.g. Graphic Design, Food Technology, Textiles), Humanities (e.g. History, Geography) and Modern Foreign Languages (e.g. French, German, Spanish).
When making your choices, you must think about what you might want to do at sixth form or college and even at Higher Education. If there is a specific Higher Education subject they have in mind, it is worth looking at some of the universities/colleges that offer that subject to see if there are specific GCSE requirements.
For example, to study French at Higher Education, in most cases the language must have been studied at A Level, and to study French at A Level, in most cases it must have been studied at GCSE.