Hello Shardanand,
You can appear for improvement exams in your respective subjects. Application would be required to be done online in cbse portal after which you need to pay required fee. Admit card would be available in Jan 2020. Then you can reappear for the examination at the date and centre that would be mentioned in the admit card. However make sure to fill up application form without any mistakes. Hope this answer helps. Best of luck!
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