Pages
If you’re viewing a document that was annotated in Pages for iPhone or iPad, you can hide, show, or delete the annotations in Pages for iCloud.
Click the View button 
in the toolbar, then choose Hide Smart Annotations or Show Smart Annotations.
Do one of the following:
Delete a single annotation: Click the annotation, then press Delete.
Delete all annotations: Click the More button 
in the toolbar, choose Preferences, click General, then click Remove Smart Annotations.