Unfortunately, diploma holders cannot directly join the second year of B.Tech programs at IITs or NITs through lateral entry. This means there isn't a specific scheme for you to get admitted directly into the second year based on your diploma.

However, you have two alternative options to pursue engineering at these prestigious institutions:

• Take the JEE Entrance Exam: Both IITs and NITs require candidates to qualify in the Joint Entrance Examination (JEE) for admission to their B.Tech programs. There are two stages to the JEE exam: JEE Main and JEE Advanced. You'll need to clear both exams to be eligible for admission.
• Consider Other Universities: While IITs and NITs don't offer lateral entry, some other universities and colleges do. You can explore these options and check their specific eligibility criteria for lateral entry based on your diploma.