Replace the public key in ~/.ssh/authorized_keys on your existing instance so the attacker can no longer unlock it with their private key. Here’s a summary of how to replace the keys mentioned ...

Nick Hardiman shows you how to set up a secure connection to an Amazon EC2 machine using PuTTY and Pageant to handle your private key.

Amazon Web Services offers up a remote development setup for Visual Studio Code developers that involves an SSH connection to leverage the AWS Cloud9 IDE and other functionality.