How do you add information to a picture on iPhone?

How to add text to a photo in Markup editor

  1. Tap the text icon (looks like an uppercase T in a white box). …
  2. Tap the text box.
  3. Tap Edit.
  4. Type the words you would like to add to the image.
  5. Tap Done when you’re finished.
  6. To change the color of your text, simply pick from the color menu.

For More Information Please Refer: https://www.imore.com/ios-10-how-use-markup-editor-photos-iphone-and-ipad