Generally, You will be getting this attendance, for every 15 days or 30 days etc from your college.

if you get attendance for every (Eg:)15 days,then you will enter total classes covered until that day.

Total Days covered in the current 15 days phase or 30 days phase etc

Holidays in the current 15 days phase or 30 days phase etc.

General number of classes per day.If number of classes are different for each day,you will enter the value of a day whose class count is maximum.Also remember to include classes with no attendance like library, seminars etc in classes per day count

Total classes whose attendance is not considered or counted like library, seminars etc in the current 15 days phase or 30 days phase.

Total classes you missed or bunked who attendance is considered or counted in the current 15 days phase or 30 days phase.