I messed up

I’m sorry to interrupt the celebrations for the O/N students, but I messed up, big time. My IGCSE exams are only three months away, and I haven’t started revising yet. I know it might seem early to some, but it feels like time is slipping away, and I don’t know where to start. I'm reaching out for help, if anyone has notes, videos, or resources for Business Studies, Economics, English First Language, Geography, History, or Mathematics (Extended), I’d be so grateful. Even just study tips would mean a lot. Thank you in advance to anyone who can share something helpful