How does AWS EC2 generate CA signed certs lively?
How does AWS EC2 generate CA signed certs lively as you know there are so many EC2 instance out there ?
EC2 never generates any SSL/TLS certificates on it's own. You can request a certificate for CloudFront or a load balancer, and it will be automatically issued, but in this case CloudFront or load balancer will terminate SSL itself.
It is possible to create an image (AMI) that will create/get/assign an SSL certificate on boot or at runtime, but this will have nothing to do with AWS.