How do I lock my Macbook at a working space?

You can also use the Apple menu as there is a "Lock Screen" option there. You can also use the key combination of: Command + Control + Q

I would not allow my devices to be left unattended in any public space since anyone with physical access may have a way of bypassing some security measures by just connecting a USB device (yes, even to a locked Apple laptop).

I have set up a hot corner to easily lock my screen instantly. you can go into System Settings > Desktop & Dock and in the right hand panel, scroll down until you see the Hot Corners button.

and then set one of your corners to Lock Screen.

the way I have mine set, all I need to do is mouse over my bottom right corner of my desktop to instantly lock my screen.

HWTech wrote:

Command + Control + Q

thanks for that. I learned something new. :)

If your Mac uses a touch-bar, a pre-programmed “button” is also available to “lock screen.”