Copyright Claim on Youtube is an issue connected to a vid you’ve uploaded on your channel. Be sure that every image and song in your creative production is not a third party property! Here is the google support page.
A god way to aviod copyright claim issues is to use only Royalty Free stuff you can easily find on libraries on the Web. There are a lot of amazing Creative Commons image archives and music libraries. Some of them are free and you can download whatever you want, with a super quality and no copyright issues. The only thing you have to do is to understand the CC license chosen by the author and verify if you can use that stuff for commercial purposes, if you can modify something and if you have to give credits.
Two good examples of free, high quality site are:
GoSoundtrack: Royalty Free Music For Youtube Video
Unsplash: Royalty Free pics
Enjoy Free Download Royalty Free stuff for your creativity