Hello @Suresh Chandra Joshi ,
Thank you for reaching out to us!
Short answer: YES, an active subscription is required to explore Azure cloud.
+A little details to it:
In order to take advantage of Azure's cloud-based services, you must have a subscription. It serves as a single billing unit for Azure resources in that services used in Azure are billed to a subscription. An Azure subscription is linked to a single account, the one that was used to create the subscription and is used for billing purposes. Within the subscription, resources can be provisioned as instances of the many Azure products and services.
Please refer to this course - https://cloudacademy.com/course/understanding-azure-pricing-and-support/azure-subscriptions/#:~:text=An%20Azure%20subscription%20is%20linked,many%20Azure%20products%20and%20services. for better understanding on Azure subscription and billing.
Please feel free to ping if you further questions in this matter.
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