If you’re running in an account that was created for you as part of an AWS event, there’s no need to go through the cleanup stage - the account will be closed automatically.
If you’re running in your own account, make sure you run through these steps to make sure you don’t encounter unwanted costs.
Delete all manually created resources.
aws autoscaling delete-auto-scaling-group --auto-scaling-group-name myEC2Workshop --force-delete
aws elbv2 delete-load-balancer --load-balancer-arn %loadBalancerArn%
aws elbv2 delete-target-group --target-group-arn %targetGroupArn%
aws ec2 delete-launch-template --launch-template-name myEC2Workshop
Finally, delete the CloudFormation stack itself.
aws cloudformation delete-stack --stack-name myEC2Workshop