WheelchairDriver

So I am looking for a way to wake the phone by voice, is it possible?

How about simply preventing the phone from going to sleep?
No need to root the phone, just put it in developer mode.

I forget the exact steps but it is something like tap Settings > About Phone
scroll down to Build Number near the bottom and tap that 7 times.
The first few times it wont look like it is doing anything, then it will count down with each tap.
This creates a new menu entry called Developer Tools, or maybe its Developer Settings which are mainly for debugging. But developers do not want the phone to sleep while debugging, so there is an option to prevent going to sleep while the phone is plugged in.
So all you need to do after that is keep the phone plugged into a charger and it will not go to sleep.

They dont dothat automatically already?
Why?

My laptop has its power settings with 101 options. You can set practically anything there. And did you know theres a google assistant for windows? Its unofficial but works and developed in parallel. You will find it and all the newest optios on reddit. I use it to do enviromental controls etc. Or I did.

Burgerman wrote:They dont dothat automatically already?
Why?

Battery fires.
Leaving a charger connected all the time, awake, and transferring data creates a lot of heat. There is an increased risk of thermal runaway, so they limit the option to debugging where the device is likely not in a pocket.
In our case, the phone is in a cradle, not a pocket, and not actively transferring lots of debug data so the increased risk is minimal.
Stay awake while on charger used to be a regular setting anyone could set even without developer mode. Then Samsung S7 recall happened.

Another great reason that I dont have or want a "smart" phone then. My flip phone works better for phoning. And thats all a phone is really any good for. The rest is just a mass marketing success over common sense. And a great advantage to the two richest companies on the planet that both happen to be data mining advertising and marketing giants that track you to death.