When Terminal says that it's done, the volume will have the same name as the installer you downloaded, such as Install macOS Catalina.Terminal shows the progress as the bootable installer is created. When prompted, type Y to confirm that you want to erase the volume, then press Return.Terminal doesn't show any characters as you type your password. When prompted, type your administrator password and press Return again.
If it has a different name, replace MyVolume in these commands with the name of your volume. These assume that the installer is still in your Applications folder, and MyVolume is the name of the USB flash drive or other volume you're using. Type or paste one of the following commands in Terminal.Open Terminal, which is in the Utilities folder of your Applications folder.Make sure that it has at least 12GB of available storage and is formatted as Mac OS Extended. Connect the USB flash drive or other volume that you're using for the bootable installer.Follow the on-screen instructions and proceed with the installation. Choose the language and click on Install MacOS. From the boot menu, select the USB drive and hit enter. It can be different depending on your computer’s model. Use the 'createinstallmedia' command in Terminal Start the computer and press the boot key like F10, F12, etc. It installs an app named Install OS X El Capitan into your Applications folder. Open this file and follow the onscreen instructions.
This is for Windows users who might have downloaded a dmg file and wondering how to extract the content, or not even knowing how and what to do with the dmg file. OS X El Capitan downloads as a disk image that contains a file named InstallMacOSX.pkg. How To Convert DMG Files To ISO Files On Windows.It installs an app named Install macOS Sierra into your Applications folder.