Hi PDF27, so my Hisense TV has a chromecast build in. So trying to connect via my Gaming PC from my room to the living room and not having much luck.The laptop doesn't cast the same way as google chromecast. Use an HDMI cable to connect your laptop to the TV.
Certain apps can be case from your phone to the Android TV (DStv, netflix, youtube etc. you will see the cast icon in the app)... Also, download the official Android TV remote control for android TV from the play-store. It will enable your phone to act like a remote.