You have like, 2 months. 3 months if you're willing to revise during your exams as well.
I would say for stuff like science: USE. THE. SPEC. make flashcards
CS: watch craig n dave.
Lang: I feel like practice is the best way here. But also communicate with your teacher, let them tell you exactly what they're looking for in your exams and then include them next time. Doing that bumped me up by 3 grades.
For stuff like maths, science (again), english. Almost everything else: DO PRACTICE EXAMS. This is after you've gotten the content down though. If worse comes to worst: at least you've memorised parts of the mark scheme lol (jk don't memorise the mark scheme). Just use the practice exams to hone in your skills.
60 days is def enough if you use them wisely.
If 1hr feels like too much, do 10, 20, 30 (mins) whatever. Just do something.
Hope this helps.