You should only use someone's music if they have explicitly (clearly) said it's okay to do so. Just giving credit is not enough.
If I were to use one of Taylor Swift's songs without a license to do so she could sue me, even if I credit her. A smaller creator may not have the financial ability to sue, but it's still copyright infringement, and they still technically could go after you. Don't be a d*ck to small artists.
There are plenty of free and legal ways to get music for your projects. If you search for music on itch.io, you can find plenty of great audio asset packs that are free and can be used in commercial projects. I've used a website called Freesound.org in the past that let's you filter by Creative Commons 0. You literally just have to look.