also, for additional context, i attempted to install etcher via the terminal using the github instructions but i got confused and i couldn’t get it to work, so i tried with the appimage and it worked - i assume it must have been a problem with me f****ng up with the terminal installation
The error message is quite explicit: Type 'sudo' is not known on line 1 in source list /etc/apt/sources.list.d/balena-etcher.list
This means the first line of the /etc/apt/sources.list.d/balena-etcher.list file starts with sudo which is not expected by apt.
This file should contain exactly this line deb https://deb.etcher.io stable etcher
Update the file or remove it, then you’ll be able to sudo apt-get update again.