Use the VoiceOver modifier on Mac
You enter VoiceOver commands by pressing the VoiceOver modifier and one or more other keys. You can set the VoiceOver modifier to be the Caps Lock key or the Control and Option keys pressed at the same time. For example, to open the VoiceOver Help menu you press the Caps Lock and H keys, or the Control, Option and H keys.
VoiceOver commands appear in help as VO-key, where VO represents the VoiceOver modifier specified in the General category in VoiceOver Utility. For example, the VoiceOver command VO-Shift-M means to press the VoiceOver modifier along with the Shift and M keys at the same time. Depending on the VoiceOver modifier you’re using, you press Caps Lock-Shift-M or Control-Option-Shift-M.
You can lock the VoiceOver modifier so you don’t have to press it, making it easier to enter VoiceOver commands. For example, when the VoiceOver modifier is locked you enter the command VO-Shift-M by pressing just the Shift and M keys at the same time; you don’t need to press the Caps Lock key or the Control and Option keys.
To lock the VoiceOver modifier, press VO-;. To unlock the modifier, press the command again.
To be able to use the Caps Lock key for typing uppercase letters when the VoiceOver modifier is set to Caps Lock, quickly press the Caps Lock key twice.