AI for 3D

A free tool for making textures and 3D via StableDiffusion: stableprojectorz.com 

Sound effects

Music for free

Advice from a forum reader: If you choose to use CC-BY stuff, screenshot all of it and keep it in a folder. Many artists have no idea what they're doing with their music once they put it into the creative commons. Many will try to remove it when they get signed (or the label will) or realize they didn't want to give it away for free for commercial use and pretend like it never existed. CC-BY licenses are irrevocable and that screenshot stands as proof that you were given both express permission and license to use the song commercially. Cover your ass.

Photo with CC license

3D models

Лицензия Creative Commons

Лицензия Creative Commons