下载并安装

dpkg -i virtualbox-6.1_6.1.20-143896_Ubuntu_eoan_amd64.deb 

错误

dpkg: dependency problems prevent configuration of virtualbox-6.1:
 virtualbox-6.1 depends on libqt5core5a (>= 5.12.2); however:
  Package libqt5core5a is not installed.
 virtualbox-6.1 depends on libqt5gui5 (>= 5.4.0) | libqt5gui5-gles (>= 5.4.0); however:
  Package libqt5gui5 is not installed.
  Package libqt5gui5-gles is not installed.
 virtualbox-6.1 depends on libqt5opengl5 (>= 5.0.2); however:
  Package libqt5opengl5 is not installed.
 virtualbox-6.1 depends on libqt5printsupport5 (>= 5.0.2); however:
  Package libqt5printsupport5 is not installed.
 virtualbox-6.1 depends on libqt5widgets5 (>= 5.12.2); however:
  Package libqt5widgets5 is not installed.
 virtualbox-6.1 depends on libqt5x11extras5 (>= 5.6.0); however:
  Package libqt5x11extras5 is not installed.
 virtualbox-6.1 depends on libsdl1.2debian (>= 1.2.11); however:
  Package libsdl1.2debian is not installed.
 virtualbox-6.1 depends on python (<< 2.8); however:
  Package python is not installed.
 virtualbox-6.1 depends on python (>= 2.7); however:
  Package python is not installed.
 virtualbox-6.1 depends on python:any (>= 2.6.6-7~); however:

解决

apt --fix-broken install

安装扩展