What are you trying to enter about the car? Why do you think you need to enter anything about Grandma buying you a car? Gifts are not taxable so you do not have to enter anything about it on your tax return.
If your grandmother paid more than $15,000 for the car for you then she will need to prepare a gift tax form--but she will not owe any tax.
GIFTS
Money that you receive as a gift is not taxable income to you, and you do not need to report it on your income tax return. Money that you gave as a gift to someone else is not deductible for your taxes.
Turbo Tax does not support the gift tax form 709, but here is a link:
https://www.irs.gov/pub/irs-pdf/f709.pdf
https://turbotax.intuit.com/tax-tips/estates/the-gift-tax-made-simple/L5tGWVC8N
https://www.forbes.com/sites/ashleaebeling/2017/10/19/irs-announces-2018-estate-and-gift-tax-limits-...
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
