When you entered the Form 1099-R, if you were under the age to be exempt from the 10% early withdrawal penalty then the penalty will be assessed on the federal tax return as a tax liability.
The Saver's Credit is based on your adjusted gross income and your filing status for eligibility.
If you are eligible then the contributions you made to a tax deferred retirement plan, such as a 401(k), your contributions would be reported on your W-2 in box 12 with a code of D for a 401(k) and used for the credit.
