I'm sorry for your loss.
Since your father died in 2018, responsibility to complete the year-of-death RMD moved to you, the heir, by operation of law.
You should report the missed RMD on your own return by filing Form 5329, Part IX. There is no interview in TurboTax for missed RMDs, so you'll need to prepare the document in forms mode. [Click the Forms icon at the top right of your screen.]
Fortunately, you can request a waiver from the penalty, and the IRS has historically been generous in granting the waiver. Please read the instructions to Form 5329 for more information. https://www.irs.gov/pub/irs-pdf/i5329.pdf