Installing QGIS (macOS)
  - Download 
qgis-macos-ltr.dmg 
  - Double-click 
qgis-macos-ltr.dmg 
  - Drag QGIS to your Applications folder
 
  - Double-click on QGIS to start it.
    
      - If you get a security warning, and QGIS won’t start, try right-clicking on QGIS and then clicking Open. (You’ll only need to do this once; thereafter, QGIS will start normally.)
 
    
   
  - Drag QGIS from your Applications folder onto your Dock (so you won’t have to go hunting for it.)
 
Whew! That was complicated… 😉