Hello student,
Basically you are saying that you have a year gap after 11th and now you want to clear your 12th exam.
See, you can easily take admission in any school for class 12th provided that you have passed 11th class. And you have to make sure that you provide the documents while taking admission for class 12th. So you have collect all these below mentioned required documents from where you passed your 12th.
In case you do not want to change School, then procedures may be less than this, as they already have your details.
These three certificates can be asked to show while taking admission to a new school.
Having said that you also be prepared to give them the reason why you took an year gap.
With all these above things, you can easily take admission in 12th again and pass it.
To check the updated syllabus of class 12th, you can go through the link below.
https://school.careers360.com/articles/cbse-class-12-syllabus
I hope this answer helps you.
All the very best!
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