I have forgot my iwatch icloud
can I change new iCloud?
Question marked as
You cannot change the Apple ID associated with your Watch until you have remembered and signed-into your current Apple ID, otherwise people could just "find" a Watch and remove the lock.
Try the steps in this knowledge base article
in order to find your apple ID
https://iforgot.apple.com/appleid
Try the steps in this knowledge base article if you forgot your Apple ID Password
If you forgot your Apple ID password - Apple Support