this isn’t much of a tutorial as much of quick links for people so they can copy and paste everything. just make sure to download the correct os agent and then use its correct filename to install it. which is on “assets” on this link Releases · home-assistant/os-agent · GitHub. (for x86 this would be wget https://github.com/home-assistant/os-agent/releases/download/1.5.1/os-agent_1.5.1_linux_x86_64.deb and dpkg -i os-agent_1.5.1_linux_x86_64.deb)
os agent: GitHub - home-assistant/os-agent: Daemon allowing to control OS features through D-Bus
thanks! any questions about the install or if you need further help just post.
EDIT: here is a post on the home assistant website that describes everything a little better and has all directions and text in copy/paste pans. Installing Home Assistant Supervised on a Raspberry Pi with Debian 11 - Community Guides - Home Assistant Community