For most TVs, use an adapter or converter to connect a headset to the TV audio jack. If the TV has a headphone jack, simply plug the headphones in the jack. Some cable boxes also feature headphone jacks for standard headsets.
To use an adapter or converter, find out what type of audio output the TV offers. Older TVs usually have the RCA audio output, which requires a standard RCA-to-3.5mm adapter. Most modern TVs have digital audio output. Use a digital-to-analog audio converter to convert the digital audio signal into an analog signal, then plug the headphones into the converter.