Question: how to connect galaxy s8 to vizio smart tv?
Answer: Obtain a Miracast Adapter like this one and plug it into the HDMI port on your TV and a power source.
On the S8, swipe down the quick menu by swiping with 2 fingers from the top of the screen down.
Swipe left, then choose “Smart View“.
Select the Miracast device in the list, and you're mirroring to the TV.