Hi there,
In the below link you can find the authorized Microsoft licensing distributors in India
https://devicepartner.microsoft.com/en-GB/connect/distributor
Yes, some websites claim that they are Volume licensing but we cannot find out the true nature of the history. It is always advised to get the key from authorized resellers. And once you get the Key you can clean install the PC and activate it with your digital license to remove the message in CMD or just select change the Key option and activate the PC.
Hope this answers all your queries, if not please do repost back.
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