Hello, I’m Nathan, and I’ll be assisting you today. My livelihood depends on your positive feedback, so your satisfaction is my highest priority.
Sorry to hear you’re having trouble.
Unfortunately modern tvs are very poorly supported - they don't give manuals any longer.
You have to have a hdmi cord to your cable/satellite box, dvd, etc for it to work.
The wifi connection is only for the apps like netflix.
If you set up the extender properly, then you just need to program the tv to then connect to that extenders network (not to the main wifi network). Go into the menu under network, then wireless, and make sure it is showing as connected to the proper network.
If you still have trouble after that, it is either from poor wifi signal strength, or just that your overall internet connection is too slow.