How to display subtitles and captions in iOS 13 for iPhone/iPad/iPod Touch

Open the Settings app .
In the Settings app, select Accessibility from the list.
On the Accessibility screen, select Subtitles & Captioning.
On the Subtitles & Captioning screen, select Closed Captions + SDH to set the toggle switch to On.
To customise how Closed Captioned + SDH look, select Style.
Choose from the preconfigured options:
- Transparent - The default subtitle style.
- Large Text - Subtitles with large text.
- Classic - White text over a black background.
- Outline Text - Large white text with a black text outline.
- Or, choose Create New Style.
If you select Create New Style, you can customise every aspect of how the captions appear:
- Text: Choose which font to use, the text size and text colour.
- Background: Customise the colour and background opacity.
- Advanced options: Set the text opacity, text edge style, and text highlight.
The preview at the top of the screen shows how Closed Captioned + SDH will appear.