I have read about VirtualBox that in VirtualBox we can run both Windows and Ubuntu in parallel, but it seems that for this we have to make one host and install the other one in it using VirtualBox.
I am already using both Ubuntu and Windows on my PC (dual boot), and I want to run the already existing ones in parallel instead of installing one of them again (I don't want to install the programs again). So is there a way that I can do this?