Hi,
For English Literature there's the cgp books, York Notes revision guides (which people argue are better than the cgp ones i've used neither for english) and websites like spark notes and LitCharts. Some things are limited on LitCharts though unless you have the monthly membership but i can get you the pdf's with the extra information on if you'd like - just message me if you'd like them i dont mind!
Knowunity is also a great app - people upload their notes, ask questions and answer them, talk in group chats specifically for each subject and each exam board and theres even things like AI Essay assisstants on there that go through your essay and tell you where to improve. I highly recommend it
I really liked the cgp books for science i found them super helpful, but i used websites like seneca, Physics and Maths tutor and youtube videos a lot of the time too - alongside past papers. If your not sure about getting the revision guides though, i suggest getting them second hand rather than buying new ones so your not spending as much money on something that you may not use as much. Theres also not much difference between the older books and the newer ones, i used my sisters cgp books and they had all the same content in as the new ones, the only difference was that the newer ones have an online version that you access with a code on the front page.
If you have anymore questions feel free to ask, but i hope this was helpful!