@Hector Caicedo Adding more information to the above response! You can also check the capacity, usage, Metrics Classic( Total request Incoming and outgoing in last days or hours) this shows the activity of the Storage account. Based on that you can decided which storage account you need to delete.
Calculate the size/capacity of storage account and it services
Check space used in azure storage accounts in my subscription
Storage insights provides comprehensive monitoring of your Azure Storage accounts by delivering a unified view of your Azure Storage services performance, capacity, and availability. You can observe storage capacity, and performance in two ways, view directly from a storage account or view from Azure Monitor to see across groups of storage accounts: https://learn.microsoft.com/en-us/azure/storage/common/storage-insights-overview
Additional information: After deleting the storage account there are few option to recover the delete Storage account, please refer to the below mentioned suggestions.
A deleted storage account may be recovered in some cases from within the Azure portal. To recover a storage account, the following conditions must be true:https://learn.microsoft.com/en-us/azure/storage/common/storage-account-recover
Enable and manage soft delete for containers : Container soft delete protects your data from being accidentally or erroneously modified or deleted. When container soft delete is enabled for a storage account, a container and its contents may be recovered after it has been deleted, within a retention period that you specify. For more details about container soft delete, see Soft delete for containers.
Please let us know if you have any further queries. I’m happy to assist you further.
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