After creating the ISO, check file size – it should be for 10.13.5. For absolute integrity, compare the createinstallmedia output’s InstallESD.dmg checksum with Apple’s official values (available via forums like InsanelyMac).
In Storage settings, add the .iso to the optical drive. macos high sierra 10.13.5.iso
Reviewing requires looking at it from two different angles: the historical significance of the operating system itself, and the practical risks and realities of the .ISO file format you are seeking. After creating the ISO, check file size –