These steps will walk you through where to create credentials (Access Key ID and Secret Access Key) on AWS to use for provisioning VMs with Ansible.
Login to the AWS Console on https://aws.amazon.com/
Under Services click on IAM to reach the IAM Management Console
On the left pane click on the users link
On the right side, pick the tab "Security credentials". Now you need to either add a new user
OR find the user you want to add credentials <- this is more common
You need to create a new access key, only then will the necessary key and key ID be shown. Make sure you save them somewhere!! (But don't upload to GitHub or someone will start mining Bitcoins on your account)
You now have your Access Key ID and Secret Access Key!