You can click on the text and start typing to make the amend yourself.
If there are more extensive amends that you need to request then follow these steps:
Highlight the specific area of text
Click on the three dots and a text box will appear for you to add feedback in
Click add comment to save your feedback
The text will be highlighted in blue
When you have finished adding your comments, you can send the deliverable back to the editor or writer using the ‘request amends’ button.