Hi,

The KCET applications are being done by the online mode, so I would suggest you to go through your emails and messages because they would have sent a mail to you with your details, once you find the user id, you can use the forgot password option to recover your password.

If you are not able to recover by this method, then try to get in touch with the KCET officials  by Keauthority-ka@nic.in and tell them your application number and email id along with the problem.