I am using Audacity for the first time. I am not an audio file expert by any stretch.

How can I insert 5 seconds of silence within an MP3 video? Separating sections of the audio file by 5 seconds of silence?

Please help!

within an MP3 video

Audacity is an AUDIO editor and MP3 is an audio format. (MP3 can be multiplexed into an audio/video file but that’s kind-of rare).

You can “extract” the audio from an audio/video file and edit it, but you’ll need a video editor (or other application) if you want to re-combine the audio & video. And, it’s generally a bad idea to do any editing/processing that changes the audio timing separate from the video because you’ll loose audio/video sync.

So before we go too far… Are you sure you want to do this? Or, maybe you should do the whole thing with a video editor so you can edit the audio & video together?