You need to open virtualbox with your virtual machine powered off，click Settings -> Advanced, set share Paste to double side 。
We have configured the SMB shared file protocol for you in the virtual machine, The directory of the shared folder is \\media\share，to view it in windows，you just need to open you windows folder manager, enter \\supernum\share in the address bar，The default username and password are the same as your login account in virtual machine.
If you modify the virtual machine’s login account, host name, or the location of the shared folder, be careful to replace the corresponding information above.
In order to improve work efficiency, we configure the virtual machine for you in the form of minimal installation. If you want the virtual machine to help you with more work, you may need to turn on Ubuntu software and search for the software you need. Here is a list of the applications we recommend for installation:
LibreOffice LibreOffice productivity suite
Thunderbird email applicatio
sqlitebrowser DB browser for Sqlite
MySQL Workbench MySQL Database Design, Administration and Development Tool
DataGrip IntelliJ-based IDE for databases and SQL
Transmission Download and share files over BitTorrent
Remmina Remote Desktop Client
shotwell picture editor
Rhythmbox music player
VLC video player