Adding alternative text to photos and images that you’ve inserted in Microsoft OneNote is a useful way to provide descriptions of visual content in your notes. These descriptions can provide important context to people with visual or cognitive impairments.
iPad and iPhone
Do the following:
On any page in OneNote, tap an image that you have inserted.
On the menu that appears, tap Alt Text.
Type a descriptive Title for the selected image. You can also add a more detailed Description of the image.
Tap Done to save your changes.
Note: To change or remove existing alt text, either edit or delete the existing information in the Title and Description boxes.