Hi there!!!

All The Chapter are important.

we can't tell,which chapter is important.

And you can't mention,which board are you.

but you prepare the previous year question papers and blue print is important.

The question will ask according to the blue print,it is useful for your examination.

don't be tensed.
Regards,
Rajdeep Sinha

Please explain for which board you are asking as there are many boards like CBSE, ICSC etc,