Hello Aspirant

A college first has to conduct exams and then the student is promoted to the next semester, especially if the student is being promoted to an odd semester. But if the student is unable to attend the exams, one of the two things can happen- if you can't write the exams because of medical issues, you can present the medical certificates and they'll promote you but some hindrances will come. Secondly, if you can't attend the examination conducted without any solid reason, they will hold you back a year and let you sit with your juniors.

The medical certificates still wouldn't confirm your promotion, there is a big chance that you will be held back because there is only a specific number of papers in which you can fail, it's either 2 or 3, in a year. The college will not hesitate to hold you back a semester/year even after you have been registered for 3rd year and you failed to give the exams.