Edit

From Audacity Manual

The main commands for editing audio are under the Edit menu (such as cut, copy and paste) and the Effect menu (you can do things like boost the bass, change pitch or tempo, or remove noise).

Audacity applies edits to selected areas of the audio track. To select a particular area, click in the track and drag the shaded area with the mouse. If no audio is selected, Audacity selects all the audio in the project window.

When playing or recording, the Edit and Effect menus will appear grayed out, because a moving track can't be edited. Commands can sometimes be unavailable for other reasons too. For example, you can't run effects until you have audio on the screen, and you can't paste audio until you've cut or copied it to Audacity's clipboard.

To Getting Started.