Click anywhere in the tab to select it.
Choose File > Save.
If the active tab contains new data that was not retrieved from a previous file or was loaded from a format that is not supported for saving, you will be prompted with the Save As dialog. For more information, see "Saving a file with a new name or format."
If you have multiple tabs open, hold Option and choose File > Save All to save all open files.
Sound Forge is a sandboxed application and needs permission to access folders on your computer. Use the Sandbox tab in the Preferences dialog to grant Sound Forge access to your folders, or use Save As to save to a folder outside the application sandbox. For more information, see "Preferences."