Ubuntu:

sudo apt install perl perl-tk
[download]

You could also install your own Perl using perlbrew. This is great if you're in a shared environment, if you better control over the versions of Perl and modules, or if you want to install modules which aren't provided by your system's package manager.

curl -L https://install.perlbrew.pl | bash
perlbrew install 5.40.0
cpan Tk
[download]

Don't forget to add to your shell's startup script as directed.