There are two versions of overdubbing, Simple and Perfect. With just your laptop and a pair of headphones, you can do simple overdubbing. Have Audacity play a backing or rhythm track to your headphones and you sing to it. Once you get to the end of the song, stop and do it again and Audacity will play the original backing track and your last vocal to you. You can sing harmony to yourself. Or not. Your choice with the SOLO and MUTE buttons on each track. And keep going until the computer runs out of room or speed.
We should remember that unlike most sound work, overdubbing demands that the computer play all the backing tracks, absolutely, perfectly and record you at the exact same time also absolutely, perfectly. Not all computers can deal with that and fixing it can be a challenge.
The gussied-up, fancy-pants version of that is Perfect Overdubbing. That one allows you to hear a perfect, theatrical mix of you and the backing track in your headphones while you perform. Like a real studio.
That one’s harder. You have to use wired headphones. No wireless earbuds for this one. You also can’t listen to the computer. You have to listen to an External Device, and you can’t use the computer’s microphone.
The overdubbing instructions mention three different hardware solutions. I have a fourth. I have a Behringer UM2 that can be used for overdubbing.
There is one Mistake That Everybody Makes. There is a magic set of adjustments you an apply to a computer to make it record internet sound. You can’t use those settings for overdubbing. You have to record directly from a hardware device like the UM2 (or a G-Track, etc.), not a software redirection program such as Stereo Mix.
If you’ve never performed in front of a recorder, your first shock will be what you sound like to others. That can take getting used to.
Audacity can’t apply effects or corrections during recording, and we can’t record from more than one thing.
Most of the maiden cruise will be taken up trying to get Windows to stop “helping you” with your voice. Particularly if you use Zoom.