Hello,
You can go for masters and after completion you can apply for jobs in the domain in which you have master degree. So on the basis of your subject you have taken you have to go for masters. You can browse for it to get the details and domain where you want to do Masters. There are many exams you can give but you have to find one where you can give and chances of having a decent rank is high. So look for one as per your domain.
Hope it helps!