Open iTunes.

How to use:

1. After the iTunes software is ready on the computer, please connect the iPhone to the computer and open the iTunes software.

2. When iTunes recognizes the iPhone, please click the phone icon in the window.

3. Please find the "Manually manage music and videos" option in the right window, and then click the "Apply" button.

4. Please click the "Music" option under the "Device" column on the left side of the window.

5. Find the music files you want to download to your iPhone on your computer, select them, and drag them directly to the "Music" column in the iTunes window.

6. Open the music to download the music you want.