Use subtitles and captioning in the Apple TV app
If you prefer specific accessible captions, such as subtitles for the deaf and hard of hearing (SDH), you can set the Apple TV app to show them instead of standard subtitles and captions. You can also customize the look of subtitles and captions.
Note: Not all videos include closed captions. This feature may be disabled on devices that already include built-in closed captioning. See your device’s user guide for more information.