Dear student,

If you want to study btech, then there is no issues even if you bring less marks in your second year. But less cgpa will affect your overall aggregate cgpa after 4th yr. Now, if you fail in btech 2nd year or got a supplementary, then you will have a chance to again give the exam and improve your scores or pass.

So, even if you for less marks in btech then don't worry. Just keep your core subjects very strong so as to get a good placement and to pass the reputed competitive exams like gate or ese, etc.
Don't take tension about the less marks in btech. But pass your exams and it will be enough for you.
So, focus on your goal not in marks. Because of you have knowledge then marks will run behind you, no you will run behind marks.