Hey Yamunadevi

Since the neet exam for 2020 has not been conducted yet there is no record or even a process to tell you exactly how many sc candidates will give the exam however I can tell you the total number of seats reserved in Tamil NAdu for SC students under SC Quota. Approximately 15% seats are reserved for SC in tamil nadu and there are total 7400 mbbs seats offered under neet inn tamil nadu hence the number of seats reserved for SC are 1110.

If you get a category rank below 1110 it is safe to say that you will get a mbbs college via neet.