SageMaker provides an easy way to train/deploy machine learning models in the cloud. SageMaker will provide a Jupyter notebook, where you can visualize/train your models and connect directly to data from S3 (API to access S3 is provided):

Here, we show the default options to create a notebook instance:

Here is the notebook panel:

And, here is the notebook (you can see examples of training models to check how the API works):