Hello,
For class 6 , you must check with the school you want admission in, whether they have seats available for the upcoming academic year and the admission process, last application dates, fee structure etc..
For class 9 , you must ensure whether that particular school accepts or recognizes the board (ICSE in your case) from which your child has passed class 8. Since you are shifting boards (from ICSE to CBSE) you will need the mark sheet and transfer certificate from the ICSE board school and check with the CBSE-school that they accept students from ICSE at that level.
Each school has their own admission schedule and norms, hence you must check directly with the school for the respective classes you are seeking admission for.
You can read more about the general information regarding CBSE admissions here. school.careers360.com/boards/cbse/cbse-admission
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