Copyright infringement

Copyright covers the expression of a work: the recording, the footage, the script, the artwork. Using any of it without the owner's permission, and without an exception such as UK fair dealing or US fair use applying, is infringement. Credit changes nothing. Neither does a caption saying no copyright intended, buying the song on a store, or the clip being short. On YouTube the consequence arrives in two shapes, a Content ID claim that redirects the revenue, and a copyright strike that is a formal legal complaint against your channel. The first is an accounting event and the second puts the channel itself at risk.