Hey, I'm not exactly new here, but just today I started to upload MP3's. I wanted to know if for playing skills I am able to play riffs from songs that have already been released. For example, I'm trying to fill out the "fingerpicking" skill, so can I play some of "Roll On" By Kid Rock to highlight that skill? Thanks for your help.
YOU (or your band) covering a commercial song is not breaking any copyright laws.
You may upload your performances, original or cover.

Using a riff from a commercial song is a perfectly acceptable way of showing your proficiency at a particular skill. Feel free, where you find it appropriate.
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