@小森 雄介 Welcome to Microsoft Q&A forum! Thank you for posting your query here!
No, In Azure storage account you cannot create directory!
However you can create create directory inside the container in ADLS gen 2 account
Use Azure Storage Explorer to manage directories and files in Azure Data Lake Storage Gen2
Data Lake Storage Gen2 provides file system semantics, file-level security, and scale. Because these capabilities are built on Blob storage, you'll also get low-cost, tiered storage, with high availability/disaster recovery capabilities.
Data Lake Storage Gen2 builds on Blob storage and enhances performance, management, and security
Create File | Create Directory | Rename File | Rename Directory
Please let us know if you have any further queries. I’m happy to assist you further.
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