Greetings!!
since you have passed class 12th , you may get Job in a good call center in Delhi, however getting a job particularly as a executive isn't possible , there might be case when you may get the Job, however getting this post directly is a bit tough, but gradually as you gain experience you may get this position as well, therefore focus on working and gaining a lot of experience and then working accordingly.
Below is the list of some international call centers in Delhi, India:
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