Hello @Himanshu Kumar Gupta ,
Thank you for reaching out to Microsoft QnA.
After activating your sandbox in the MS Learn Module, please login to the Azure Portal and navigate to Directories, and you will see the directory of Microsoft Learn Sandbox. You need to switch to this Sandbox directory from your default directory to be able to access your sandbox and create your azure resources accordingly.
Please refer to the following link for further details - faq.
Hope this helps. For any further queries, feel free to reach back and tag me.
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