You can redirect your sub-domain to another URL using below given steps

1) Login to Cpanel

2) Click on Sub domains

3) Select sub domain and click on “Manage Redirection”

4) Enter URL say “http://test.com” and save.

Now your sub domain will be redirected to test.com

Note: If you wish to have file name redirection (example: http://test.domain.com -> http://redirecturl/test.html) be sure to end a trailing / on the end of the url.

You can remove redirection using “Remove Redirection” button.