make copy of one of other ".desktop" file in /usr/share/applications
and edit it for your application
below is "Obsidian.desktop" file for launch Obsidian application
#!/usr/bin/env xdg-open [Desktop Entry] Name=Obsidian Exec=/home/gim/bin/Obsidian Terminal=false Type=Application Icon=Obsidian StartupWMClass=ObinsKit Comment=Obsidian-icon Categories=Note;