@Nagashree Balasundaram Based on my understanding, you want to create a new group and add and manage users via REST API. Use Group entity to create a new group or manage existing groups and the same has been documented in docs: https://learn.microsoft.com/en-us/azure/api-management/api-management-howto-create-groups
For adding and managing users to a group, use Group User entity. Here are some PowerShell references: New-AzApiManagementGroup and Add-AzApiManagementUserToGroup. I hope this answers your question and feel free to add a comment if you have any other questions. We would be happy to assist you.
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