After getting the degree in M.Sc Physics you can try in Govt and private both the organizations. Few of them are given below -

Bhabha Atomic Research Centre (BARC), Oil and Natural Gas Corporation (ONGC), Bharat Heavy Electricals Limited (BHEL), National Thermal Power Corporation (NTPC), Indian Space Research Organization (ISRO) etc.

Apart from this, you can also apply for the competitive exams conducted by UPSC like IAS,IPS, and IFS depending upon your interest and potential.

Also, you can try in private sectors as there is very good opportunity for the students who are done with the M.Sc physics like IT companies such as Infosys, Wipro and CTS recruit M.Sc Physics graduates for software jobs, you can try in Energy plants and automobile industry is also open for you like Maruti Udyog, TATA Motors and Tech Mahindra etc.

Note : As you have many options open in front of you so better to focus on one in which you have maximum interest and in which you can give your best.

Good Luck!!!