Never connect a smart TV to the internet. Always buy them from a store with a good return policy. If it doesn't work without an internet connection, then return it.
I've had the same early smart TV for about ten years now. The greatest thing that happened to it was the WiFi dying. I suspect I wouldn't have it anymore if that weren't the case.
It's a 42" Samsung if anyone is curious, and the WiFi just... Stopped working.