In TurboTax Free Edition, click on Federal Taxes, then Deductions & Credits, then scroll down to the various deduction headings (you may have to click on "Skip to see all tax breaks" to display them).
Select Education, then click on Expenses & Scholarships (Form 1098-T) and follow the prompts to enter your education expenses from your 1098-T form. If your school did not issue you a 1098-T, then answer "no" when TurboTax asks you if you have the form. TurboTax will then ask you questions to qualify for a waiver of the form requirement. Assuming you qualify, then you'll be able to enter your expenses.
TurboTax will ask you questions and make the determination which of the education benefits you qualify for (and which benefits you the most).