Keypair update using EC2 instance

When deploying and connecting to an Ec2 instance through a key pair,
Adding a separate KeyPair (multiple) for colleagues,
After deleting the existing keypair, you may need to register a new keypair.
(For security reasons, a specific keypair must be changed every 90 days)

In this case, can it be controlled through the Morpheus UI page rather than directly modified inside the OS?

You can achieve that via tasks. Eg: Ansible tasks to deploy keys.