When colleagues create and assign you a task in Outlook, you receive a task assignment request. You can let the sender know whether you accept or decline the request.
In the Reading Pane, click Accept or Decline.
If the Reading Pane isn’t turned on, open the task request and click Accept or Decline.
To include a comment with your response, click Edit the response before sending. If you don’t need to add a comment, click Send the response now.
Accepted tasks appear on your Outlook task list.