How do you fade a track in using Audacity?

To fade a track in Audacity, first select the portion of the audio you want to fade in by clicking and dragging over the waveform. Then, go to the "Effect" menu and choose "Fade In." This will apply a gradual volume increase to the selected audio, creating a smooth transition from silence to full volume. Finally, you can play back the track to ensure the fade in sounds as desired.