It is vitally important that your loved one's TV ad Cable STB (if any are correctly set up so that when they turn on, they g to the right input / content source, for example, the Cable Box or Antenna.
The settings are mostly in the TVs, and are now called "Power," "Display," "Home Screen" or older devices, "Input / Source" Settings. A few very new Cable STBs based on Google or Android operating system also have them.
Please see our list below, but understand they may not apply to your specific brand device(s) and you may need to look in your TV manual, online resources, or call the manufacturer.
Thank you for your diligence and please appreciate our limited ability to provide support for all these other devices and software systems.
Google TV - same for all brands - see also Dish Hooper
Dish Hopper - Scroll to "Power Settings"
Cogeco Epico - see also Dish Hopper
All Others, like Insignia, Toshiba, etc:
Use your TV branded remote then look in the settings, then follow the onscreen prompts to set your Input / Source / Power On selection as appropriate (different brands may use their own terminology).
You may need to refer to your manufacturers manual, or google your TV brand, followed by something like "home screen power on settings"