How to create a VO recording for submission?

I'm very new to CCC, and also, to voice over acting. It's something that a friend told me I should consider and look into, and so I am here. I found a few that I would like to try, but I don't know what to do as far as recording my voiceover. I run a podcast and use Riverside for my podcast. I don't know if there's a way to use Riverside to play the YouTube video that needs the voiceover, and then record myself doing the voiceover. Again, sorry for sounding ridiculous, but newbie here. Any and all help is appreciated. Really want to get started. Thank you!