QuickBooks Self-Employed (QBSE) uses simplified or standard method when calculating taxes.
Right now, the accounting method used is Cash basis accounting where it based on the transactions entered in the system and how these are categorized when calculating taxes.
To learn more about how QBSE works, you can visit our QuickBooks Community website. You can check some articles that are designed to help you get acclimated with the software. They can be accessed at the following link: QuickBooks Tutorials.
If you have any other questions concerning QuickBooks, you're always welcome to come back again by commenting below. I'm here for you. Take care.