connecting wifi to a TV (Sony) SMART

Not sure about T-Mobile and new devices (outside of my phones/Macbook).  I have plugged the T-Mobile gateway into my existing WiFi router, so that I don't have to make any network changes on my end, and everything just works as is (i.e. unplugged cable modem + ethernet jack, plugged in T-Mobile gateway + ethernet jack into WiFi router).

I get better range with my own gear, and a lot more control.

I got a new tv and want to know to know how to connect it to gateway so I can get rid of my cable company. I'm not good with electronics. 

@Greenhats Find the Network section in the TV's settings menu.  Look for something like "Set up connection".  Let the TV scan the available wireless networks.  Select your T-Mobile network and type your network password with the onscreen keyboard.

Greenhats here. I did everything you said and my tv will not connect to gateway. I tried 6 times. Should I be connecting anything to the back of the tv or should I have my internet line checked. Any suggestions

Hola @Greenhats, I'm assuming you are trying to make a wireless connection. I have a TCL Roku TV. Every smart TV is a bit different, but in my case the setup is Settings > Network > Set Up Connection > Wireless.  It will then scan for available networks.  Once you choose the "T-Mobile" network you would enter your network passkey. It should then connect to your network.  Are you getting an error message after entering your passkey?  There wouldn't be anything that needs connecting to the back of your TV, unless you are making a wired connection (Ethernet).

@Greenhats Are you able to connect your other devices to the T-Mobile network? Assuming you are, are you getting a good signal near the back of the TV?  (Use your phone and the Speedtest app.)  If that is the problem, try moving the gateway to somewhere closer to the TV, but still able to connect to the tower.

Next try unplugging the TV for at least 30 seconds.  Then try the TV setup again.

The next thing is to read this article -- https://www.lifewire.com/how-to-fix-vizio-tv-wont-connect-to-wifi-4685906 -- though some of it isn't relevant to the T-Mobile gateway because it has very few things we can change.  I can tell you how to set up a second T-Mobile network (on the same gateway) with WPA/WPA2 security if you can't get the TV to connect to the default network (which has WPA2/WPA3 security.)

Yikes, I think you found the wrong app - maybe an imposter.  Delete it.  We'll assume that the wifi signal is reaching your TV. 

Here are a couple of help videos.  If you are still having trouble, you might want to contact Vizio support.  

https://support.vizio.com/s/article/Connect-TV-to-Wireless-Network?language=en_US

https://www.wikihow.com/Connect-Vizio-Smart-TV-to-WiFi 

Having same trouble with my new Sony Google TV. TV says the internet is connected by it doesn't connect with the TV. Please help. I have got a decent signal (120ish) on my other devices in the same room). 

Greenhats here

 I have a Vizio tv. It says to start over and do again. I am trying to connect it to tmobile gateway. Apparently it's not connecting to something. Thank you for helping me. The tv didn't come with a manual but it's on the menu of the tv.

Greenhats here

 My cell phone is connected to it and that's OK. I'll move my gateway closer to tv even though my connection is excellent where's is at.