My dell venue 8 pro is very hot during chargging and the charging light is not on

Dell Venue 8 7000 7840 Factory Reset Sequence

(reboot)shut off and turn on to see if you still get message

Dell Venue 8 Pro frequently drops WIFI and bluetooth

Venue 8 Pro WiFi and Bluetooth issues

Reboot the entire system clear the virus

Check whether the battery have enough charge. If it has below 40% of the total power needed, the tab won't start up. Recharge it fully and try. http://electronicshelponline.blogspot.com/

Train your son to follow instructions and then call Dell Tablet Technical support ao 800-308-3355: They are in India so speak slowly and clearly while using formal English - they don't always understand American slang.

Seems to be a common problem.
You are on the right track with holding down power button.

1. Hold down for 20 secs, Wait 5secs, hold down for up to 10 secs, it may turn on before then.

2. Does the screen have a dim glow, even though there is nothing on it?
Let it discharge itself so the glow is gone, may take some hours.
Plug it into charge for at least 30 mins.
Try to turn it on.

More info here
http://answers.microsoft.com/en-us/windows/forum/windows8_1-performance/why-wont-my-dell-venue-8-pro-windows-tablet-turn/50573983-8cb7-4770-bf5c-478e63ec5cf8

"right click" by touching and holding on them until a square appears - you'll find the "delete" option in the list that opens.

Check to make sure that the keyboard is fully charged.