Assuming you've installed the AWS SDK for Python:
pip install awscli
pip install boto3
Next, run aws configure
on your laptop or server to add your AWS credentials.
For details, see https://docs.aws.amazon.com/cli/latest/userguide/cli-chap-welcome.html
Then you should be able to run this script to list files in the bucket and download them:
python download_s3.py