Hello sridarsini,
   
  Actually neet cutoff varies depending on various factors like no of applications, no of seat intake, difficulty of paper, etc . So normally we can assume the cut off by considering previous year cutoff.
   So according to the previous year cutoff for getting admission in Balaji medical college Chennai under unreserved category you should have minimum 50 percentile. In 2018 the cutoff marks range was between 119 to 691 so it may be around it.

Thank you!!