Hope you are doing well.
As per the documentation, create user using MS graph API will not support any Odata query parameters.
At a minimum, you must specify the required properties for the user. Based on the valid request payload it will create the new user and return the predefined property values in response irrespective of values mentioned in $select parameter of Request API.
If you want, you can use OData query parameter $Select with Get method type.
Hope this helps.
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