Hello everyone, I apologize in advance for my bad English, I have always sung in my life and in many bands, but I have never found the sound for me and for the projects that I would like to implement. On your site I noticed some “free for commercial use” music bases and I would like to know if, by recording my voice on the bases and / or modifying the bases themselves, will it be possible to record them on a CD and publish them on spotify?

Hi, the quick answer is Yes.
You’re referring to those licensed under CC-BY
creativecommons.org/licenses/by/3.0/ (which the beta browse list shows as “Free for Commercial Use” as a filter option)

Under CC-BY, you must credit the creator/ owner/ source in the manner specified. This should be reflected on your CD label, Spotify write-up etc in a reasonable way. For further clarity, it’s a good idea to refer to this set of CC FAQs at creativecommons.org/faq/

Hope this helps.