can't open Balena after extracting zip file

Just extract/unzip the zip file. Then open the unzipped folder “BalenaEtcher-linux-x64” and tap the file “balena-etcher” (do not confuse it with the shortcut balenaEtcher next to it). After opening balena-etcher you might get a pop-up what to do. To execute it or to execute in a terminal. Just execute it. Voila.