You can try the registry edit.
One important thing you need to know is that changing the registry is pretty risky since it may give rise to irreversible damage to your computer if you operate it incorrectly. Thus, you had better create a system image before proceeding.
Navigate to the Windows folder based on the following path:
From the right panel, double-click on the NoAutoUpdate (REG_DWORD) and set its value to 1. Click OK to confirm. After that, restart your computer to stop Windows 10 update download.
Hope this resolves your Query !!
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