How do I add car rentals used for doordash in the update vehicle information?

Welcome and thanks for your first post here in the Community, @johnson-nobleqb-. I've got you the steps to enter and update the info of the vehicle in QuickBooks Self-Employed. 

To do this, I'd recommend using a web browser in setting up your vehicle for the first time. Here's how:

1. Go to your profile icon, then select Vehicle info.
2. In the Vehicle info dropdown, click the tax year.
3. Enter the name and year of your vehicle, then enter the amount of purchase in the How much did the vehicle cost field.
4. Select an Ownership status option, then select the date you bought the vehicle.
5. In the Date placed in service field, select when you started using it for work.
6. Use the Estimated business miles slider and make an estimate. This setting helps you with tax estimates. You'll track the actual mileage with the app.
7. Select Save.

For future reference, you'll want to read through this article: Fix mileage tracking issues in QuickBooks Self-Employed. It helps you learn about the things you need to do in case you'll run into problems tracking your mileage. 

I'll always be here if you need more guidance in adding and tracking your mileage, @johnson-nobleqb-. Take care!