Hii!
To take admission into patna women's college you need to score a minimum of 50% marks in class 12th in relevant stream from a recognised board of education. Admission is given mostly by PUCET entrance exam. The cuttoff varies as per different categories. For general category, the cutoff touches 75-80 usually each year. For OBC it is in 60s and ST / SC it is 50-55. It may vary in different years.
Hope this helps.
Good luck!