What is typically involved on a tax return taxes and credits line 16

1040 lines 16-24 are taxes you owe and some credits you might qualify for.  You need to look at schedules 1-3.   Line 24 is the total tax on your income after certain credits.  Any W2 or 1099 withholding is on lines 25a and 25b.  

If you have a tax due it is on line 37.  A Refund is on line 35a.  

On the Form 1040 Line 24 that is your total tax liability before any tax payments you paid are deducted.

On the Form 1040 Line 33 is your total tax payments and credits.

If your total tax liability is greater than your total tax payments then you will have taxes owed and that is the amount on the Form 1040 Line 37.

If your total tax liability is less than your total tax payments then you will have a tax refund for the overpayment and that is the amount on the Form 1040 Line 35a.