While you can generate an unlimited number of tracks on the free plan, you'll have to upgrade your membership if you want to download the song. The sample tracks are all original pieces fed to the AI by Soundraw's producer team, and you can play, edit, share, and like each sample. The tracks you're shown are based on tags (which you can further modify) that show specific samples. In the Create Music page, where you can modify the length, tempo, and select the mood of the track, you're essentially creating a guideline.
Soundraw, the older sibling of Ecrett, operates somewhat differently to other AI music generators.