This question already has an answer here:

I tried to install webmin to my 18.04 erver. i folloved DigitalOcean 's method.

When i did

sudo apt install webmin

The outpu was like:

   Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 webmin : Depends: libauthen-pam-perl but it is not installable
          Depends: apt-show-versions but it is not installable
E: Unable to correct problems, you have held broken packages.

Thank you all your answes, Peter

marked as duplicate by N0rbert, Community Aug 17 '18 at 17:47

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  • Webmin is not in the Ubuntu repositories...for good reasons...so the amount of support we can offer is limited. The Digital Ocean method you linked to is awful and hacky. Undo all of it, then search this site for the many similar "How do I install webmin?" questions. – user535733 Aug 17 '18 at 17:05