The operation of adding audio to background music is as follows:

Tools: opporeno7, PFJM10, Swift Text to Speech 4.5.0.

1. The quick text-to-speech download is completed.

2. After opening the software, find the audio mixing function in the "Audio Editing Tool".

3. Then import the recording and background music that need to be synthesized.

4. In this way, new audio can be formed.

5. The audio can also be converted into text through this software.