If you are installing Ubuntu 18.04 in VirtualBox 6, Windows 10 Or Windows 10 pro, and facing an issue of the blank screen not moving forward. Please disable Hyper-V from Windows feature on and off.
Step 1: Open Windows search and “Turn Windows feature on or off” and select “Turn Windows feature on or off”
Step 2: Uncheck Hyper-V and click okay
Step 3: Click okay and restart Windows.
You will be now, able to install Ubuntu 18.04 in VirtualBox 6 on Windows 10 machine.