Good day, @jlmcclellan_1126.
You can enter your tracked mileage one by one and categorize it. Also, you have the option to record only the total recorded miles and categorized it. Just make sure to keep a copy of the detailed one for audit purposes.
Here's how you can enter your tracked mileage manually:
Go to the Miles menu.
Choose the Add trip button.
You can read through these articles to learn more about tracking your miles in QuickBooks:
Swing by here if you have other questions. I'm always here to help.