itch.io free music packs
Game Music Library- free music, new themes every month
Credit line
"Game Music Library- free music, new themes every month" by wiktorthemes (https://wiktorthemes.itch.io/game-music-library-free-music-new-themes-every-month) Licensed under CC BY 4.0 — https://creativecommons.org/licenses/by/4.0/
Where to put it: CC BY: game credits or video description. CC0: no credit needed, but composers appreciate one.