Vijay;

The Preparatory Courses is a one year residential programme and as the name suggests prepares the students to be eligible for the B.Tech or Dual Degree Courses at the IITs. The candidates are being selected from the non qualified candidates in the ranking order of JEE.

speaking of the ease of preparatory course, it's neither tough nor easy. The essence of hard work will matter the most. Around 30-40 students are allowed to take admission in several IITs from this course.

It compromises of 2 semesters. You will have to study Math, Physics, chemistry and English in this time. The toughness of the paper will be mostly similar to that of 11th and 12th. If you pass the two semesters with a good CG , you'll be allowed to get admitted in IITs. And I'd like to suggest that if you work a bit hard you can easily get a higher CG .

Hope this helps and all the best!