The law that extended the tuition and fees deduction, and many other provisions, for 2018 through 2020 was just passed a few weeks ago. The TurboTax software has not been updated yet to reflect the changes in the law. The IRS has not finished issuing revised forms and instructions for the changes, and TurboTax has to wait for that. Try again in a few weeks.
I had the same trouble in 2018 with my college expenses. Look for form 8863. It's called American Opportunity and Lifetime Learning Credits. I was able to write off everything listed on all my semester's detailed breakdown of what I paid for just to call myself a college student.