copyright infrigement

Hey yters, so I'm really tired of using the same music over and over from the audio library but I'm not sure where else to get music so that I don't have any copyright issues. I also noticed that a lot of videos have popular songs, like the other day I saw one with Shape of You in it.. I it was...

I run a channel that has 30,000 subscribers. One of my subscribers informed me a few days ago that someone was taking material from my lectures. I reviewed his channel and it's almost comical .. he has the exact same titles and names and clearly took my stuff. Even the playlist is in the exact...