Mock grades

Well done on your grades! I think as they are, you will be skilled enough to take further maths A level - I know people who got 7s in gcse maths and are now doing well on the course. I think it's possible to get 9s in your gcses at this point too - focus on exam technique mostly at this point. For maths you just need to do questions, try the grade 8/9 questions at the end of the paper mostly. With enough practice your grade will go up quickly.

For english literature I think I tried to find techniques I could confidently analyse every time e.g sounds, complex sentences, iambic pentameter. It's good if you can get confident at analysing structure because that's something which will help in both lang and lit. Good luck with your gcses!!

how do you revise?

The English language was probably the hardest for me - I only got a 5 last year but what I did was practice a lot. I did and currently do questions regularly to give to my teacher to mark. I did one or two full papers in the lead up to my mocks because timing is something I really struggle with so that helped quite a lot.
For sciences and maths, I do a lot of questions to practice exam technique. I make notes on harder and lesser know topics such as capture-recapture and then put the technique into practice.
For Spanish, we get a Quizlet every week and I try to learn the vocab, even though I may get lazy sometimes...
Practicing reading and writing is important. For speaking, if you write model answers you can just recycle them in your writing which was a big help during mocks as it cuts down on the workload.
Idk if you do geography or comp sci, so it would be a waste for me to explain but if you do I can tell you
Hope this helps!

i got 7+ in everything but language(German) and maths, but i feel like my revision takes too long compared to other people who end up getting better grades with less. Well done tho

Honestly, those grades are amazing and you should be proud! Most students go up by at least one grade between mocks and the real exams, so I don't think you'll have any trouble in raising your grades if you really, really focus on revision. I'd suggest making sure you're revising the topics that you aren't as confident on, instead of going over what you know many times - It's a trap students easily fall into.
I always found mindmaps incredibly helpful - I had binders full of them by the end. Big A3 sheets for main topics and A4 for subtopics etc.
Make sure you look at the mark schemes so you know what you get awarded marks for!