@Sarbpreet Kaur
You can have up to 1000 local users per storage account. You can add a local user by going to Settings, select SFTP, and then select Add local user. Walking through the prompts you will also be able to setup the users permissions for the storage containers. At this time permissions are only supported at the container level and it is not possible to setup permissions for virtual directories.
Please see Configure Permissions for a walk through of adding a user and setting up the permissions.
Hope this helps! Let me know if you have any questions or issues.
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