You don't need two PC's to stream to be a successful streamer, but it does have 2 big advantages:
Cody 'Frizzable' Baumgartner is an American Fortnite player who previously played for Polar Ace. He is currently a Twitch Streamer.
Frizzable uses the Logitech G502 Proteus Spectrum gaming mouse.
Frizzable uses the Razer BlackWidow Chroma gaming keyboard.