In an annotation, the title part will be the front of the Anki card, and the content part will be the back.
Export your annotations
Open Google Play Books on your device.
Go to Settings.
Turn on Save notes, highlights, and bookmarks in Settings. This ensures that any annotation you save will automatically sync to your Google Drive.
Open Google Docs or Google Drive, navigate to your annotations file, and download it. The downloaded file might be in PDF format instead of DOC. You can use online tools like Adobe Acrobat to convert the PDF to a DOC file. Such as Adobe Acrobat
Use this website to convert all your notes into an Anki deck
Download and import the .apkg file into your Anki app