any tips?

This is probably so your teacher can sit with you just before the exam.

any tips on what to do before a gsce exam?
some of my exams are in the morning at 8:45am, we were told to come to school at 8am for breakfast but i have breakfast at home instead so i try to prepare myself for the exam

Firstly let yourself be well rested and calm - know that all the effort you've put in will pay off!
Don't do too much revision beforehand as it can overwhelm you, instead just maybe test yourself on a few equations or use a couple of flashcards, but don't overdo it.
Check if you have all your equipment and make sure you have them with you, so you don't stress about it later on your way to school.
Hope that helps and good luck with your exams, you got this!