Thank you for reaching out to Microsoft Q & A forum.
The 403 Forbidden error appears because the Microsoft Learn sandbox allows deployments only to the pre created resource group (e.g., learn-xxxx). You won’t be able to create a new one like SQresource within the sandbox.
To proceed in the sandbox, please run:
Set-AzDefault -ResourceGroupName <your-sandbox-rg>
If you'd like to create your own resource group, consider using a Free Trial or your personal Azure subscription instead.
Also, note that Units 1, 2, and 4 cover theoretical concepts, while Units 3 and 5 provide hands on exercises.
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