@Vij Thanks for posting in our Q&A.
Honestly, I'm not familiar with Powershell script. Based on my research, the "New-AzureADDevice" cmdlet can create a device in Azure AD. Please refer to the following article:
https://learn.microsoft.com/en-us/powershell/module/azuread/new-azureaddevice?view=azureadps-2.0
No. It doesn't mean that the device will be managed by intune once the device is joined to Azure AD. Azure AD join and intune enrollment are different things.
Hope it will clarify something.
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