Only the remote power button works for the TV

We have a Charter Cable remote. It acts like it's paired, turns the TV on and off, but nothing else works besides that. And I've tried to re-pair them, which didn't do anything.

I've checked the remote through my phone's camera, and I see the red light through the front, but idk if that's what I should look for the see if it's the remote and not the TV.

Please help, it's been three days of constantly being yelled at by my mom because the TV won't go to the menu to be switched to hdmi and then being ordered to “fix the remote then" when I don't know anything about this stuff (which I've told her, each time) and thank you!