Broken LCD screen, battery problems, how to fix it?

My Samsung Galaxy Amp 2 has multiple issues right now. One is a cracked LCD screen, not the glass of the phone. The cracks were seen invisibly black, was seen in this photo because I think the glass of the phone is broken. It was the LCD or the LED screen.

Then I tried to jump-start my phone’s battery using a 9V battery

into my removable battery and my phone’s battery was working, with full revival energy in the battery.

Once I charged my phone with a revived battery, something was wrong. It doesn’t have the screen on or the phone wasn’t charging. It also doesn’t vibrate and the charging box doesn’t heat. When I did these steps below, it doesn’t work.

1. Charging my phone
2. Removing my battery and putting it back again
3. Pressing any button with the power button

At least an hour after charging, the phone’s removable battery drained because the screen wasn’t on. And my phone wasn’t charging either. I jumped start my phone using the 1st and the 3rd sockets rather than 1st and 4th as seen in the WikiHow image compared to my phone’s image:

(Sorry for the focus, red means positive while black or blue is negative)