I got 70 marks in her mains and 976 in ts board exam can I get seat in sastra university
Yes, you have chances to get Sastra university based on your marks.
You can also get private college in other states like: Haryana, UP, West Bengal, Punjab, Rajasthan, Maharashtra. Most of the states have reservation for other state students in private colleges based on JEE Main score/rank. You need to apply separately for them.