You can absolutely do it! It will be difficult, yes, but you've already proved to yourself that you can catch up. I'd suggest making a checklist (use your specification for this) of all the work you've missed, and learn it in any way you can. You might want to make a revision schedule now-ish, and an intense one at that.
Focus on understanding everything first of all, so just review all the work you've missed in terms of 'do I get this concept?' if you do, great. Move on. If not, talk to a teacher, find videos, anything. I'd suggest doing a couple hours a day (maybe a bit more) until start of March - ish.
From that point, you'll want to focus on learning everything you need so you can pass - essentially, the Foundation specification. teachers often put in a lot of unnecessary extra learning, so I wouldn't suggest trying to use your classmates' notes. keep to the limits of the specification. do this continuously until your exams, but try and cover everything by middle of April - ish, I'd say.
Then, if you're taking the higher papers, start to extend your learning and memorisation to the stuff you need for higher. Luckily, there isn't too much extra learning (although people like to pretend there is) so just focus on getting it done. This should probably not be your priority though, because with limited time you need to focus on passing primarily.
Practice papers! As soon as you have a vague grasp on the foundation information, start doing papers as much as possible. you will have missed out on feedback from your teachers, so hand them your past papers - I'm sure they'd love to help you and will be happy to give you feedback. I do a past paper or two every week, and give around one or two a month to my teachers. the others, I self-mark, but I'm sure you could get away with giving in more papers because of your situation.
All in all, I'm absolutely certain you can do it. Don't expect all As or anything, but you'll succeed, I bet. Hope this helped, and good luck! X