There are many software for adding music, the simplest is Format Factory, VideoStudio, Phantom Factory, etc. Format Factory is relatively simple. After you add the music, test whether the steps match the music. Look at where the frame number is and adjust it according to the beat number of your music. VideoStudio is the same, but with one more channel decomposition (that is, decompose the original channel content and delete it, then add the music you need.) Add the music and play it to see if the pace matches the music. That's it.