On a computer or mobile device, open a web browser and go to yt.be/activate. This is the official YouTube activation website. On the web page, you should see a field where you can enter the activation code displayed on your smart TV. Enter the code exactly as shown on your TV screen. Once the activation is successful, you should see a confirmation message on your smart TV and the web browser. You can now access your YouTube account on your smart TV. You should be able to view your subscribed channels, playlists, and recommended videos. https://www.tvlinkcode.com/activate-youtube-on-roku-apple-lg-sony-samsung-and-fire-tv-the-ultimate-guide/