Change the host name:

https://www.vultr.com/docs/how-to-change-hostname-on-a-vultr-cloud-server/#How_to_Change_Hostname_without_Erasing_the_Server

Root user commands: https://www.cloudpanel.io/docs/v2/cloudpanel-cli/root-user-commands/#:~:text=Password%20Reset,newPassword!

Change Host:

https://www.globo.tech/learning-center/sudo-unable-to-resolve-host-explained/