Next, create a virtual hard disk now and click create ( and select next VDI option and click next ).Now Select memory size ( and recommend memory size is 4000 MB ) and click next.And new popup window is the open first field you need to write your OS Name you can write any skip the second field because it’s already configured if you want to change the installation directory you can change it by clicking the second field, let’s move the third field and choose the type of operating system ( Linux ) and move the last field and chose version ( Debian 64 ) and click next.After opening the VirtualBox you need to click on the new button.