Download and install Radarr
Radarr provides a native installer for every major platform. Go to the official download page and grab the right version for your system. On Windows you get a standard .exe installer. On Linux/Raspberry Pi you run a one-line install script from the Radarr wiki. The installer sets Radarr up as a background service that starts automatically with your computer.
Linux script asks for a user/group — just press Enter to accept the defaults unless you have a specific media user set up.
If the service does not start, run: sudo systemctl start radarr && sudo systemctl status radarr
