Follow the steps here.

If you encountered the problem that the downloaded Install High Sierra file only has 19MB.

Then, check your OSX version and App Store version.

update

For me, I need to update to El Capitan 10.11.6 and update App Store to download the full file (after deleting the 19MB file, and re-download).

If you’re downloading macOS High Sierra, use a Mac with High Sierra, Sierra 10.12.5 or later, or El Capitan 10.11.6. – How to create a bootable installer for macOS

Keep following the link, and finally change the screen resolutions using this.

For me, I changed it to 1920x1080.

Further Reading

  1. How to Install macOS High Sierra in VirtualBox on Windows 10 | How-To Geek
  2. Fix VirtualBox macOS High Sierra Screen Resolution (1920×1080 – 4K – 5K) | wikigain
  3. How to create a bootable installer for macOS | Apple Support
  4. 如何製作 macOS 10.13 High Sierra USB 系統安裝隨身碟 | AppleFans

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