Virtualbox Official Website
Note :- I really recommend to install after the Oracle VM VirtualBox Extension Pack because with it you can use the 3D option, fullscreen mode, sharing folders between guests and host, and many others.
I recommend to use the package from stock repositories because in theory, it’s easier to compromise VirtualBox repo than Debian repo for example. So :
apt install Virtualbox Virtualbox-ext-pack???
On Linux, i recommend to change the default directory for machines.
Verify that you have the extension pack :
For example, i will present how to create a space :
1) Click on New
2) Define the name, you can customize also the machine folder here. The type and the version are important because they use certain parameters and if you select for example 32-bit, you can not use after 64-bit system !
3) My recommendation is 2048MB. Minimal requirement for Linux is 512MB in general, for Windows 7 1024MB and for Windows Vista/8/10 2048MB
4) Prefer VDI format :
5) I absolutely recommend Fixed size because in Dynamically, the space grow when needed but never reduce !
6) I recommend to use at least 25GB. The minimum size for Linux is 8GB and Windows 15GB.
Finally, you can add shared folder between host and guest in Preferences > Shared Folders > New :