If the inherited IRA was kept in an inherited IRA account and the funds were not distributed, you probably shouldn't owe anything. It's possible that you might have had to take an RMD (Required Minimum Distribution). The plan's custodian should have informed of that.
If the funds were distributed to you, and you were not 59 1/2 or older, you would owe 10% of the funds distributed.
In ADDITION, the amount of funds distributed would be included in your taxable income. When combined with your other income and deductions, the tax would be computed on the final amount of taxable income.
The following is a link to distributions from IRAs, and includes inherited IRAs.
https://www.irs.gov/publications/p590b/ch01.html