Install Catbird Linux v2.0 and later with Calamares. It is installed and ready to use.
Install older versions of Catbird Linux using one of the methods linked below. Depending on how you want it installed, the task can take a few minutes (dd to a USB flashdrive) or an hour or two (rsync clone to a slow hard drive). I suggest using Ventoy to create a bootable USB or SDcard for running Catbird Linux. However, it is more convenient for many users to instead boot the iso in a virtual machine. Go for it; do whatever works for you and your computing situation.