To preview a candidate's CV, simply click on the CV icon within a Candidate record.
This will open a preview panel on the right hand side of the screen;
Within the preview panel, you can zoom in/out, scroll between pages, click through to the candidate's record using the 'View Profile' button and download or print the CV;
By default, only Super Users will have the ability to download or print. You can also Edit or Create a Formatted CV and the information for this can be found here.
Super Users do have the ability to give other user types this functionality by going to Settings > User Management > User Permissions;
Just tick the box next to each user type then click Save before leaving the page: