Do I have to file tax return for 2nd job

You have to report all income. Period.

This is a crazy question. You must report income in the year you earned it. I am sure your employer sent you a W-2 (which also goes to the IRS). Go to a tax professional to prepare the return right. Ron Cappuccio

You report all income earned in a year on the return for that year. If you chose not to report it on the original return, you will end up owing penalties and interest when the IRS catches up with you. The penalties and interest will more than offset anything you might earn by investing that money instead of paying tax on it.

All of your income must be reported on your tax return, including the income from your second job.