GCSE physics is an extremely tough GCSE, and only the best and brightest students get the best marks on their exams. The physics of gcse is best known for its high level of mathematical content and the many equations you must remember. This is because anything could come out of the GCSE physics specification. I am doing the AQA course and I got an A in my AS and it is by far my favorite subject.
It's a big jump from GCSE as are all A-levels, but as long as you're good with numbers and aren't particularly stupid, it's very doable. There are some difficult subjects and strange new ideas, but nothing ridiculous. You should have studied Science and Mathematics before. You must be curious to know how the world works and be prepared to establish connections between what you can observe about the world and scientific principles.
You have to be willing to work hard and be challenged. You must be willing to participate in regular practical sessions. I got an A* in GCSE physics, but as soon as I started Level A I realized that it was worth a lot in comparison. GCSE Physics covers many interesting and fundamentally important areas of physics, including forces and motion, electricity, waves, space and astronomy, sustainable energy, radioactive decay and radiation.
Combined Science IGCSE explores the basic principles and applications in biology, chemistry and physics and leads to a single award rating, an IGCSE, based on your performance in all three subjects. While you could get a decent GCSE in Chemistry or Biology without being able to make your time charts, Physics requires you to be good at Mathematics, and Mathematics is literally the hardest thing ever. I'm not saying this because I was good at physics, because I'm not a stinky nerd, but I'm also the one sitting here writing this introduction, while people who were good at physics are making lots of money cold, hard, delicious, building bridges, or designing apps, or running banks, that's how they are transferable their skills are. GCSE Physics helps you understand how the world works, from everyday things like microwave ovens and mobile phones, to the birth and death of stars and what happens inside atoms.
At GCSE I got good grades in all three Science subjects, and I had always enjoyed physics predominantly above the others, so I chose Physics at the A level.