The method for downloading songs from the USB flash drive is as follows:

1. Connect the USB flash drive to the computer and ensure that the USB flash drive is correctly recognized and mounted.

2. Search in the browser and find the music resource you want to download.

3. Click the corresponding link to enter the song page.

4. Click the "Download" button or link to save the song to your computer's hard drive.

5. Copy or cut the downloaded music files in the file manager to the computer directory connected to the car's USB flash drive.

6. After the file transfer is completed, disconnect the USB flash drive from the computer and pull it out safely.

7. Insert the USB flash drive into the corresponding USB port of the car audio system.

8. Wait for the car audio system to automatically detect the music files in the USB flash drive.

9. Select and play the song you want to listen to through the buttons on the control panel or steering wheel.