Installing HA supervised on Debian 11 is an officially supported method by HA.
Why would you do that you ask?
– Install on any machine that supports linux, making you flexible about the hardware
– Can be installed on an old laptop. The battery will help to keep your system alive on power outages.
– You will be able to run anything on that machine in parallel, if you would like.

This guid is for experienced linux users, you must have basic understanding of what you are doing with basic linux commands.

Let’s Get started!

Step 1

We need to be sudo, update the system, install docker and other utils.
If you are starting from a clean installation, you can run each of those commands one at a time.
If not, I guess you know what to do regarding those packages you already have installed, but if not – you don’t need to install them again 😉 

sudo -i

apt update && sudo apt upgrade -y && sudo apt autoremove -y

apt --fix-broken install

apt-get install jq curl avahi-daemon apparmor-utils udisks2 libglib2.0-bin network-manager dbus wget -y

curl -fsSL get.docker.com | sh

Step 2

Luckily, some brave soul created an installation package of HA OS-agent for us, so we will just need to download it and install it.
Run each of those commands one at a time.

wget https://github.com/home-assistant/os-agent/releases/download/1.2.2/os-agent_1.2.2_linux_x86_64.deb

dpkg -i os-agent_1.2.2_linux_x86_64.deb

Step 3

Now we will need to install home assistant supervised.
Make sure you are sudo first:

sudo -i

Execute the following commands one at a time.

wget https://github.com/home-assistant/supervised-installer/releases/latest/download/homeassistant-supervised.deb

dpkg -i homeassistant-supervised.deb

You may be prompted to choose a machine type during the installation process, if so, choose generic-x86-64

That’s it! You are done installing and now should wait a few minutes, then visit your local machine IP on port 8123 – i.e. http://192.168.1.100:8123

More details can be found on the original HA community post by kanga_who