DVB TV HAT on Raspberry Pi 4

The installation instructions of the TV HAT says I should run the “sudo apt-get install tvheadend” but in the hassio-terminal I don’t have access to the apt-commands. Can this device be installed in some other way? I tried to login via cmd-prompt and SSH in windows with no luck. Thanks in advance.

I think you’re going to have to start over and install the Pi operating system (Debian Linux) first and then put the HA software and your TV HAT on that.
I would consider using 2 Pi’s… one dedicated to HA and another as your TV HAT platform.

Thanks for reply. Initially I installed the image with Home Assistant OS on the Raspberry. I was hoping there was a way to install the TV HAT as an Device/Service or Integration somehow without starting all over.