Hi there!
Yes, of course. 2 years is more than enough time to achieve high grades. However, it's crucial you go through topics often so you don't forget them. This will develop your recall skills so that closer to your Year 11 exams all the knowledge and understanding is there and you would just need a refresher/look over your notes.
Also, make sure you organise your work/revision well and manage your time. Plan ahead, have an idea of when you'd like to start revising for each set of mocks/exams you'll have in the next 2 years. Don't start too early as it will burn you out, but don't start too late as you will become overwhelmed with so much revision.
Do take some time to rest after school every day and take breaks whilst you're studying! Do not let school take over your life completely, we all have off days where we just can't revise or do any work and instead spend time with friends/family, going out and enjoying ourselves.
This is some general advice; if you'd like some extra info on how to revise English/Maths/Sciences, I'd be more than happy to give some subject-specific revision tips and recommend resources!