How can I install webmin ?

    You can't for two reasons:

    a) There is no package manager to install packages like webmin

    b) The userspace filesystem is decompressed from SYSTEM on each boot, and is read-only

    It's possible to install the Docker add-on and the pull a webmin container, but webmin is going to assume a standard Linux distro with a normal filesystem layout where everything is read-write, so you'll find most (all?) features are non-functional.

    Why do you think you need webmin?

    I see.

    Well, mainly I would like a dashboard that shows me in one screen things like HDD and CPU temps, how much disc space has been used, system load, etc.

    I use Webmin on every other Linux box in the house, and I kind of rely on it to tell me that HDD temps are OK (I live in a hot climate).

    You can clone the embedded Estuary skin folder to /storage/.kodi/addons then modify addon.xml to change the name so it doesn't clash with the embedded version, then mod as you like.

    You're also welcome to experiment with webmin via docker, but LE is not a derivative of any other distro and our layout is rather non-standard which normally trips up tools that expect conventional Debian/Fedora packaging.