usually you have to go to the settings to turn it on. every menu is slightly different but for newer android versions you normally have to go to the WIFI settings and then select "advanced WIFI" from there. the new menu has the "WIFI direct" option which should see the TV and allow you to select it to connect to it.
if it works, then you'll be looking at your phone's screen mirrored onto the TV. now simply open/start whatever app you want to view on the tv.
kind of generic directions and your menu may differ but this seems to be roughly the standard way for android in the last few versions. i don't have your phone to verify but seems to be the case for other phones i have had/seen.
If it's a Smart TV and has support for wireless video, nothing you need to install. If the phone sees a compatible device, you will see a screen cast icon, see this from Netflix as an example https/help.netflix.com/en/node/2331