Can i use the 3d files from opengameart.org and music from freesound.org to create a 3d movie to publish in youtube? Can you explain the legal terms tat I have to concern?
Yes, every asset here could be used to create a movie, the limits come down to if you can charge for it, if you have to distribute your source material, and if you have to credit the artists. GPL license would require that anything you create be released under the same kicense. The CC non commercial license limits your ability to sell, or make money from, the movie. Any of the CC-BY licenses require to to credit the artists.
CC0 is the least restrictive and can be used without limitations, and doesn't require crediting the artist.
Of course, you are responsible to reading the licenses to clarify things, but that is my understanding of the licenses.
Note that all licences on here allow commercial use (CC Non-commercial isn't allowed here).
CC BY-SA would also likely (as far as I can tell) require that the resultant movie is released under the same (CC BY-SA) licence.