indusvo Unfortunately, the description is consistent with a hardware failure. You might want to take the device to a repair shop to see if it looks that way to an expert.
Meanwhile, it should be possible to get the device to turn off. If you apply power, it should display a screen with a yellow alert indicating it is about to boot a non-Google OS. On that screen, tapping the power button should pause the boot process. If so, let it charge for at least several hours.
Once it's charged, holding the power button down for a long time (up to a minute) should turn the device off.
Can you try those two steps and report back? Probably the next step would be a safe-mode boot, but first let's make sure you can get the device charged and off.