Hi !

If you don't like the college alloted to you during the ALL INDIA Counselling process , just don't go the college for document verification and further counselling process. Your name will be discarded automatically by the official authorities , there is no need to go the college and ask for a exit. Just don't go the college at first place, that's all.

All the best !

Check out the following link for more information regarding counselling process:

https://medicine.careers360.com/articles/neet-counselling