Hey Makarajothi

To get a seat at Government Siddha College you need to score minimum 550 marks in  National Eligibility cum Entrance Test. However things will highly depend on your category and domicile. Also due to the coronavirus pandemic saying anything about the cutoff is far fetched still for an idea try to score atleast 550 in neet as this was the cutoff last year for general category.All the best!