Open Disk Utility (Utilities Disk Utility).
The steps are straight forward: Double click the DMG so it mounts.
PeaZip supports reading.ISO and other common disk image formats, such as Apple DMG (commonly used on macOS / OSX operating systems), UDF, and viewing many virtual machine disk image types including VMDK VMWare virtual disks, QCOW2, Oracle VDI, Microsoft Virual Hard Disk VDH files, as well as general purpose image formats as IMA, IMG, and MDF. Not doing so will result in a vmdk that can be attached to a VM at install time but any attempts to add it to a VM at a later point. If you have such a image make sure you resize to the nearest megabyte first then convert it to vmdk format. A word of caution when using qemu-img to convert images for use with VMWare Fusion - Fusion doesn't like disks that aren't sized exactly to the megabyte.
