Hello Ranjan Sahoo ,

With 66 % you are not eligible for JEE Advanced and even if you appear for Improvements then too you must be aware that you won't be eligible for admission this year.

Now if you know the above then coming to your question:

You will have to appear for all the subjects. But all he subjects means:

P/C/M + Language paper + Optional subject

(total of 5 subject)

Hope that helps!