Convert CDA to FLAC

You can't directly convert CD Audio Track Shortcuts to Free Lossless Audio Codec Files (.cda to .flac conversion), as CDA files do not contain any audio data. They are merely shortcuts referencing audio tracks on a CD.

You can, however, rip the CDA files off the audio CD and export it in FLAC format. This can be done with a dedicated tool or (online) conversion utility, such as Total Audio Converter or fre:ac, which should allow you to rip off CDA audio from a CD and export it in FLAC format.