Command + Tab — Switches to the last used app among your open apps.
Command + Y — Uses Quick Look to preview the selected files.
Command + Left Bracket ([) — Goes to the previous folder.
Command + Right Bracket (]) — Goes to the next folder.
Control + Command + Q — Locks your screen.Shift + Command + Q — Logs out of your macOS user account.
Shift + Command + I — Opens iCloud Drive.
Shift + Command + N — Creates a new folder.
Shift + Command + O — Opens the Documents folder.
Option + Command + L — Opens the Downloads folder.
Option + Shift + Command + Delete — Empties the Trash without confirmation dialog.
in browser Ctrl + E : clears the address bar so you can begin typing.