Hey Raj:)

If you passed 12th in 2025 and want to give an improvement exam in 2026.the application forms are  usually released a few months before the exams ,since exams are held in july-august the forms may release in april-may based on previous years, but the exact date depends on your board.

2025:

For CBSE,the forms were available from may 30 and the last date to apply  with a late fee was june 19

Form filling:

You can fill the form online through your board's official website or portal or you can fill through your school, providing your previous roll number,marks, subject you want to improve etc and you'll also need to submit the required documents.

Its best to check your board official notification for exact dates and rules,as some boards allow private candidates,while others require school enrollment.