Hello aspirant,

The most common problem faced by students is of the food. South indian states use coconut oil to which eastern students are not habituted. Their diet is a lot different. 

The other problem the language. You have to get used to the common language as hindi isn't used much there and even their english accent is different. 

Thirdly, the climate of certain regions is a lot different from other parts of India. It is very hot and humid. 

However, the people there are really friendly and good and that's what matters the most. You'll cope up in no time.