Hello,

The eligibility criteria for upsc states candidates need to pass bachelor's degree in any discipline from a recognized university, there is no specific aggregate required in this case, you need to attain 21 years age and can apply even in the final year  of graduation, now the thing is if you plan to do upsc, pursuing higher studies don't make sense, because after graduation you'll be automatically eligible, now you can also appear for upsc after completing PhD, if you fulfill the age limit criteria, but then you have to decide what you want, in my opinion, if you're more intersted in teaching or research  career go for PhD, else you should  appear for upsc after graduation.