User blog:CloverLeafNine/Can Someone Tell Me...

Can someone tell me how you add audio to a video?

I know, this is a stupid question, but I'm an idiot.

I make a lot of UTAU cover, and I wanna post 'em on YouTube, but I can't figure out how to add the music to a video.

Can someone just tell me a program I can use and I'll be on my way.

Thanks!