Hi @eswarpd001,
You can use the ListDashboards API operation to get the list of all dashboards. I believe namespaces are for users and groups. I don’t see the option to specify the namespace in the request body or as a URL parameter.
You can use GenerateEmbedUrlForRegisteredUser or GenerateEmbedUrlForAnonymousUser to get the embed URL.
For more information about embedding, take a look at these resources: