Deductions & credits

 It depends. The IRS does allow you to enter actual travel expenses in lieu of mileage.

1. Log into Turbo Tax
2. Go to federal>deductions and credits>Charitable Donations>Donations to Charity in 2020
3. When you find your charitable donation on the summary page, select edit
4. Select add a donation underneath that entry
5. Select mileage and business expenses
6. Next page will say Enter your mileage and travel expenses for XXXXX.
7. At the bottom, the page will say other travel costs.  Enter the amounts here plus a brief summary of your travel costs.
8. Here is  a screenshot on what this looks like.