Have you lived 1 million seconds if you are 12?

Answer 1

Yes.

You have lived 1million seconds by the time you are 12.

You've lived more than that, but 1million seconds is included in those 12 years.

its also been included in your first couple of weeks, but still the answer is yes.

Answer 2

Far more than that. You have lived more than 1 million seconds by the time you are 12 days old, not 12 years. By the age of 12 years you have lived nearly 380 million seconds.