Change the behavior of the modifier keys
You can change the behavior of the following modifier keys: Caps Lock, Control, Option, and Command. (On macOS 10.13 and later, you can also change the behavior of the Function key on keyboards that have an Fn key—except keyboards with Touch Bar.) This is useful if you’re familiar with a keyboard layout that’s different from your current keyboard.
For example, the Control key on UNIX computer keyboards is located where the Caps Lock key is located on Apple keyboards. For experienced touch typists, this can be awkward. Changing the behavior of the Caps Lock key to Control solves this problem.
Choose Apple menu > System Preferences, click Keyboard, then click Keyboard.
Click Modifier Keys, click the pop-up menu for each modifier key you want to change, then choose an action.
To return the keys to their original settings, click Restore Defaults.