I google’d for this, and it seems that it’s pretty straight forward.

$ curl https://packages.microsoft.com/keys/microsoft.asc | sudo apt-key add -
$ curl https://packages.microsoft.com/config/ubuntu/16.04/prod.list | sudo tee /etc/apt/sources.list.d/microsoft.list
$ sudo apt-get update
$ sudo apt-get install -y powershell
powershell
$ pwsh
PowerShell
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PS /home/jj>