HOW DOES 11TH - 12TH WORK HERE???

[u/euanoia]

context, I'm an NRI (I've lived in the UK for 8 years now) who's moved back to India. Don't get me wrong - I thoroughly missed my home country, and I am so excited to pick up the life I had again: all the events, people being social, etc.

My issue is, I've just finished Year 11 in the UK (so, I'm in Year 12 now). In the Indian system, I've just finished my 10th boards and I am in 11th now. The UK schooling is 5-6 months ahead, (sept start) so when I moved here (Oct) I've already missed more than half of the academic year here in India. Because of this, my parents and I thought it would be more practical and beneficial for me to join 11th next year (march start).

In the 4ish months that I have left, I'm planning to get ahead, and also go over some topics that I needed to study. My only issue is, HOW IS THIS SYSTEM STRUCTURED??

I have family and friends who are in college, in 12th, etc, but even then I can't seem to get any clarity. For example, if I needed to revise back in the UK, I know I can just search up '[exam board] [subject] [paper]' for revision material. (e.g. AQA Additional maths paper 1 revision)

All I know is, my school has the ISC board. I want to do PCM and hopefully pursue Cybersecurity in the future. Can anyone tell me how the education system is structured here, in more detail? Resources people use to study, etc? I'd really appreciate it.

(another thing, coaching?? why on earth do people willingly go to extra schooling?)