I am sure you have already created your account on Azure. You need to upgrade your account in order to use the resources, such as Cosmos DB, virtual machines, and so on.

At the time of writing the book, Azure provided us with free credit of around 13,000 Indian rupees (approximately $200) for a month to try out their services at first upgrade!

Open Azure portal (https://portal.azure.com) and log in using your Microsoft account. Once you have logged in, click on any services, for instance, click on Cosmos DB's icon from the left menu.

You should be viewing the subscription popup; click on that and fill in your credit card information. Microsoft will charge around 2 Indian rupees to verify your identity. They will not charge you further.

Once your account is verified, you can see your subscription in the account section. Refer to the following screenshot for reference:

Let's go ahead and create an Azure Cosmos DB.