I have created a AWS workspaces for some users. is there any way we can add IAM role with AWS workspaces same as we do with EC2 instances, So that they do not need AWS keys and can access AWS services as per IAM role attached with workspace?
No. Obtaining credentials via IAM Roles uses the Amazon EC2 Metadata Service, which is not available for Amazon Workspaces.
You will need users to add IAM User credentials to a local credentials file.