Hello Yash,

If you are not allotted a seat in any medical college in Round 1 

Then New registration facility is also available for Round 2.

Round 1 registered candidates need not to register or pay again for Round 2.

Choices submitted in Round 1 will be treated as null and void for Round 2.

Fresh choices submission for seat Allotment in 2nd Round is mandatory.

If you are allotted in the Round 2 then you can continue with further process and If not then the procedure for seat allotment ends.

For more detailed information you can refer to this website - https://medicine.careers360.com/articles/neet-counselling