It should not be listed in the WiFi. That isn't quite how it works. You need the "Chromecast" connected to your tv. It then must be using the same WiFi as the the other devices (tablet, etc.) will be using. After that you need to make sure you have downloaded the "Chromecast" App and installed it on your tablet (or any other device you want to use it on). You can find it on "Google Play" under the name "Google Cast". Then you can find "Chromcast Setup Instructions" for android here from Google Support...
It should not be listed in the WiFi. That isn't quite how it works. You need the "Chromecast" connected to your tv. It then must be using the same WiFi as the the other devices (tablet, etc.) will be using. After that you need to make sure you have downloaded the "Chromecast" App and installed it on your tablet (or any other device you want to use it on). You can find it on "Google Play" under the name "Google Cast". Then you can find "Chromcast Setup Instructions" for android here from Google Support...