Hi, I did AQA economics back in 2022 and got an A*. If your school has a subscription, UpLearn was very useful for revision (but I didn't find it useful for learning content for the first time, it didn't go into too much depth). I did most of my learning in the classroom and then just did a lot of practise questions. Planning essays was the most useful learning activity imo. It ensures that you gain a good understanding of the models, diagrams, and the theory you need to examine policy.
In short, my best advice is to just start working through past exam papers sooner rather than later. Physics and Maths tutor has past economics exams that you can use, and there are plenty of other resources online for other exam boards.
Finally, very strong recommendation for Econplusdal's YouTube videos. They explain things with as much depth and clarity as you could ever hope for. As a current Econ student at uni, I still go back every now and again to refresh my memory of basic topics using his videos. (he also separates his videos by exam board, so you you could look for only his OCR content if you wanted to).