I filled improvement exam for all 6 subjects what if I fail in one exam then would my whole improvement marksheet will be replaced with previous one or mark for that one particular subject only?
You haven't mentioned the Board exams that you are enquiring about. But in General, if you have failed in one subject and cleared it later, the first marks sheet would show that you failed in that subject and when you clear the subject, you would get an individual marks sheet for just subject mentioning your marks and mentioning as "PASS".