I don't think it can be done easily like you want. My suggestions would be to feed one of your S24 inputs with the audio out of your phone
along with the mic in the other input. Or use software to record the youtube as an mp3, and then import the mp3 into your daw as a track. The problem occurs because once you select the S24 as your laptop interface, you won't be able to route out of the laptop headphone jack at the same time.