Hey, I took basically the same GCSEs except astronomy (didn’t even know that was a GCSE) and I achieved 7 A*s, 2 As and a B.
I only took the new spec for English and Maths but I’m warning you that they are much MUCH harder than the old spec so you’ve really got your work cut out for you x
Firstly, you’re only in Year 9. Don’t worry about anything! It all goes downhill from year 11 onwards hahaha....
Anyway, from my personal experience, you don’t have to start revising until Year 11 February half term. I can honestly admit I did nothing up until then and I still got top grades. You probably won’t even remember much of what you learnt in Year 9 by exams anyway lol
Just make sure you go over PPQs as much as possible, especially for triple science. It’s important to get your exam technique to perfection so you can manage your time effectively when it comes to exams. Also it may be worth investing in revision guides early, that way you’ll be more inclined to go over content your unsure of rather than just ignoring it. It’ll save you stress later on!
Your exams have little to no coursework as far as I’m aware so that’s one less thing to worry about.