If a Peer review or Upward review step are included in a Review cycle, there are a few different ways in which the responses can be made available to you.
Your admin will have chosen one of the following while setting up the review cycle:
Once a response has been made available, it will be visible under the Completed Reviews tab in My Reviews.
To get here, first click on My Reviews in the sidebar:
Then, click on the Completed Reviews tab at the top:
From here, you can choose which cycle you wish to view responses for and expand it to view the answers.