How to Set hostname in MacOS

Step #1: Open The Terminal

Open the terminal and execute the following

Set ComputerName

ComputerName is the user-friendly name for the system

scutil --set ComputerName  NewHostName

Set LocalHostName

LocalHostName is the local (Bonjour) hostname

scutil --set LocalHostName

Set HostName

Hostname is the name associated with hostname and gethostname

scutil --set HostName

Step #2: Reboot

Reboot your system to apply and see your changes.