Not all DMGs are created equal. Here is a checklist to find the one:
: Even if you don't have an "unsupported" Mac, you can use the High Sierra Patcher tool to download a complete, untouched copy of the macOS High Sierra installer directly from Apple's servers . macos high sierra 10136 dmg google drive best
(Drag the DMG file into the Terminal window to auto-fill the path.) The Ultimate Guide to macOS High Sierra 10
Downloading macOS High Sierra 10.13.6 as a DMG from a third-party source like Google Drive is a common but macos high sierra 10136 dmg google drive best