Dear student,

As you have taken as PCM with computer science as extra subject instead of biology and i am considering that your curriculum for class 11 has already started and you are doing your classes.

In these kind of matters i would recommend you to contact your school principal if you want to change your subjects again as this would be a hectic process and it won't be done very easily. It would be better if you contact the principal and have a meet with your principal including your parents if possible.