Steps to  play music for the duration of your slide show in PowerPoint:

• You can include a music in a presentation and have it play across slides in the background.
• If you wish to incorporate music from the internet in a presentation, you must first download it to your computer.
• Select Audio and then Audio on My PC from the Insert tab.
• Browse to the music file you wish to utilise in the file explorer, then pick Insert.
• Select Play in Background on the Playback tab with the audio icon selected on the slide.
• The audio file starts immediately during a slide presentation when you select Play in Background, and it also plays throughout numerous slides.

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