https://aws.amazon.com/premiumsupport/knowledge-center/recover-access-lost-key-pair/
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-key-pairs.html#replacing-lost-key-pair
1. write down the instance ID, AMI ID, & Availability zone of the original instance
In the root device field, take note of the device name for the root volume(for example /dev/sda1 or /dev/xvda).
choose the link & write down the volume ID in the EBS ID field(vol -XXXXXXXXX)
Note:
Availability zone
Instance ID
elastic IP
create an instance with same AMI
2.deattach the storage from original one and attached with new one