From SEEDLabs
Download the digital ocean download for the 20.04 machine and click the link below for instructions.
Ubuntu 20.04
ISO image
Go to this link in which you will be prompted to download an iso file. Create a folder in your home directory for VirtualBox images, then create a folder inside of that one called ISO images. If you are interested in getting this machine up and running in VirtualBox, then message me and ask for help, if you even need it.