Tutorial: Launch and configure a WordPress instance in …

The default password to sign in to the administration dashboard of your WordPress website is stored on the instance. Complete the following steps to connect to your instance using the browser-based SSH client in the Lightsail console, and get the password for the administration dashboard.

https://lightsail.aws.amazon.com/ls/docs/en_us/articles/amazon-lightsail-tutorial-launching-and-configuring-wordpress