Creating a bootable macOS USB installer from a DMG file depends on whether you are using a Mac or a Windows PC. On a Mac, the standard method involves extracting the "Install macOS" app from the DMG and using the native createinstallmedia
Once Terminal says "Install media now available," your drive is ready. To use it: Shut down the target Mac. Plug in the USB. create mac os x bootable usb installer from dmg
diskutil eject /dev/disk2