AR + Unity + Voice Commands

Hello

I've read a lot of posts. I've looked through most tutorials on the web and still do not know how to solve my problem. Please give me advice how to use the voice command like "Next" and "Back" to change the view of the current scene? I want to create an assembly instruction where the operator can only use voice control. Please help me. It must work on android, any app? script? advice how to use an app to connect it with buton function?

Probably the reason why I still do not know...

AR + Unity + Voice Commands