Hello,
CBSE board will take care of it. They will handle how to conduct improvement exam prior to admission process starts. As of now application form for some UG programs has opened. It is not closed yet. They have just started the process and it is unknown when they will process to next step. Results of other state board are not released yet. Many process are pending so they will decide how to process it with students health as first priority.
Admission is done on the basis of selection criteria which may differ previous year trends. It may be lower this year. You will get college as per your qualification merit. So not worry about it.
Hope it helps!
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