How to add music from Apple music to an MP4 movie earlier created on Apple iMovie
I created an iMovie movie earlier from my photos library and saved it in MP4 format. I would now like to add music from my Apple Music library as a background. Sorry I didn't do it while in iMovie, but too late now.
How might I add music to this movie?
Thank you.
iMac 24″, macOS 14.6