Hi Shubham,
Firstly congratulations on finishing your bachelor's degree. Talking about Master's degree, I would recommend you to join a course which you truly enjoyed in Bachelor's, say either physics or chemistry or anything else. Because usually after Master's completion people directly apply for various entrance exams and start getting placed in good companies etc. So if your marks and grades are not good then it will be a waste of your 2 years and you won't get any jobs. That's why it's on you on which courses you ant to choose. Usually all pure science courses are good but nowadays people get jobs faster when they do technology related courses in their pure science course like Biotechnology or bioinformatics or geophysics etc. So I would recommend you try for those type of courses which have a touch of technology.
Good Luck