If you want to try out different types of response, have a look through the Alexa SDK response builder docs: https://ask-sdk-for-nodejs.readthedocs.io/en/latest/Building-Response.html.
We have only used S3 to get data that we manually stored; there are other methods that allow more S3 functionality: https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/S3.html.