Linking from a Wiki Page to Another Website

1. In the page you want to change, click Edit. 
2. At the place on the page where you want the link to appear, paste the URL. Confluence automatically converts the URL to a link. 
3. If necessary, edit the resulting link text. (Use the Source Editor to edit the first or last character of link text.)
4. If necessary, edit the link address:
   1. Click the link text. A row of buttons appears.
   2. Click Edit. The Edit link dialog box appears. 
   3. Select Web link. Modify the address for the website. (Modifying the link text at this point might not work correctly.)
   4. Click Save. 

For every link in which the website is external to the U.S. Government, you must add an exit disclaimer as described in Marking Links as External to US Government. 

Also refer to Linking from a Wiki Page to a Wiki Page.