Not sure which question you are asking. If the iCloud account is associated with the Apple ID in question, then you cannot change it, and they both would have the same password. To see if the iCloud account is linked to your Apple ID, go to: Apple - My Apple ID on a computer, or go to Settings>your name>Name, Phone Numbers, Email on your iOS device and see if the iCloud.com address is listed there under Reachable At.
If it is, then it would use the same password as your Apple ID.
If it is saying that your Apple/iCloud ID is locked: If your Apple ID is locked or disabled - Apple Support