loads of royalty free music around in SoundCloud - most just ask you to credit the artist with a link to their social pages so as to not get a copyright strike in YouTube. You can also search YouTube for royalty free music and most will have a link to a location to download the file and again they will ask you to credit them as the artist.
Thats what I do to find music for my vids. This way the artist gets exposure too so its a win win.
What may be in YouTube’s audio library may not be on Meta’s or Tiktoks, meaning you can’t willy nilly post to all platforms and not expect to hit a copyright claim.
Unless you’re being very specific with ‘cut to the beat’ type stuff, Just add your audio in the app that you’re using and conform your videos for that platforms user base.
Youtube/facebook - longer form videos, you may have to use a different soundtrack beause what’s licensed by Google (YT) might not be licensed by Meta. (FB) If it’s literally drone only and not a whole lot else, keep it about 3 minutes, regardless of how cool you think it is, a drone only video of anywhere get’s boring to most people within a minute, older people may hang around but most will click off, check your analytics.
Insta/Tiktok - a minute or less and use their music library.
Unless your channel is monetized, you can use pretty much use any music from YT. You may get notice of copyright from YT but its not classed as a strike. Usually states - The track is copyrighted but the owner allows it to be used in YouTube. This is not a strike - or something like.
just found another resource.
not sure how popular it will be but also there is a cost for downloading the tracks. but i have just used the instrumental version of Firestarter by the prodigy on a video and got no strikes from youtube. so could be useful for popular tracks if they have what you want.