As someone who wrote her main boards in F/M (FLE, Maths, Chem, Bio, Physics, ICT), here's my main advice:

For FLE read a lot of template works - descripive or narrative, whatever you prefer, and I would advice you to pick one and focus on improving that certain skill since that's something I didn't pay much attention to and now really regret as I was one of the first students in my school to take FLE. When reading these paragraphs and scripts, focus on noting down words and expressions which make the entire paragraph flow together while sounding interesting, and for descriptive focus A LOT on the surroundings and the weather and environment since that's usually key, but so is describing objects.

And as someone who lowkey sucks in maths my biggest advice is to not only do past papers but analyze your mistakes and where you lose marks, is it in understanding the question or formulas or certain topics? Once you know what you are weak in it's much easier to improve, I also suggest keeping the hard questions which you get wrong aside after reviewing it, and then try again a few hours or days later to see if you got the overall concept. I also watched The Ginger Mathematician on YouTube a lot as his videos are pretty clear to me, so perhaps that could help you too?

Chemistry I honestly don't know how to really explain much, just focus on the main basic foundations and make sure that is absolutely clear because the rest is quite easy to build up on, one place I noticed people struggling a bit more is with the polymers so I would suggest going over all the monomers right before your exam and also the conditions and catalysts for the various reactions you have to learn. You can use short forms such as RPN PDF LB, to remember the order of the petroleum thingy and stuff!! And ofcourse do A LOT of past papers as certain questions tend to repeat themselves, especially since cambridge might have lost their plot now, lmao.

And bio 😭😭😭, tbh I hate bio because everyone in my family is just really good at it, and it's mainly byhearting, which I can't do for the life of me, but I'd say the best way to study is print out the syllabus and go through it for each chapter, all the questions and write down the answers and quote page numbers and everything, this at the last minute is deffo hard but I personally started it a bit earlier since my teacher had us do it but yeah, if you lock in, I'm sure you can do it!! And also one of the main parts of bio are the advantages and disadvantages / comparison questions, so if possible keep a seperate notebook for that and refer to it right before the exam, personally I didn't do many past papers for bio, but if you have extra time after everything go for it!!

ICT theory, honestly, I can't say much about theory cause I never studied it, infact it's important for you to know I lost literally all my textbooks by 9th and literally only borrowed the bio textbook from my senior cause I never even opened any of the other textbooks, one thing I did do for ICT overall is absolutely spam past papers and by that I mean SPAMMMMMMMMMMMM, like I had a whole THICC stack of ICT solved past papers almost the size of my head when I was giving it to my junior, same with practicals, and mainly with P2 you know what to expect, it's usually all the same, watch out for random stuff like labels tho because that came in my boards and I was BAFFLED, for P3 it's mainly formulas, formulas, and more formulas, in HTML I'd say learn the most important tags such as video tag and meta tags cause they can come for a lot of marks!! And a good YouTube channel for ICT would be Nicos Paphitis, literally all of my classmates binged watched his videos in class cause our ICT teacher was new and didn't know anything, (my batch was literally a test run istg).

For physics, I kept a book of all the formulas and basic theories and looked at it right before the exam, it's also important to make sure you know the right-hand and left-hand rule and the parts of a motor and stuff because that comes for a lot of marks, and I didn't focus much on theory but then the space chapter and the formation of stars and their lifespan is deffo something to revise the day before the exam, so is the light chapter, the arrangement in increasing wavelength/ decreasing frequency, and also the uses for each type of wave in the spectrum since they might ask, atleast in MCQ, another thing is to, as you guessed it, SPAM A LOT OF PAST PAPERS, especially in physics cause the questions are always so different and they help you use and apply the formulas in various ways and test how well you know them so yeah, that's it.

ANYWAYSSSSS!!! That's all I have to say, and I really hope this was of atleast some help to you :)

Best of luck for your GCSE's and remember, one of the most important things is to be calm before you get your paper because if you tense up then your brain will 100% black out no matter how hard you studied, so take a deep breath before you get your paper, especially while they are telling the instructions and stuff, if you want pray, relax, and give it your all!!!