@manish verma You should be able to use FileSystemClient.GetPathsAsync to achieve this. On our GitHub page we have sample code which allows you to list all the directories. Combining that with sample that lists all the directory contents should get you the results you need.
Hope this helps! Let us know if you have further questions or issues and we will be happy to assist.
-------------------------------
Please don’t forget to "Accept the answer" and “up-vote” wherever the information provided helps you, this can be beneficial to other community members.