Can you set up a different account with a different username (with the same underlying email address) that is not ky email?
If you want to maintain the same MS account but use a different username for your laptop setup, you can create a new alias for your existing MS account, keep your original one as the main account.
But the alias and the underlying account are still tied together, and any settings synced to the cloud will still apply.
If you want new laptop to be completely separate from your family computer and the existing Microsoft account, you can create a new Microsoft Account by a new created Outlook address.
Or you just sign in Windows via a Local administrator account.
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