Ki Energy is your lifeforce energy.It is the energy you use [as spellcasters] ,to charge things.Ki energy could be used for almost anything!
WHERE IS MY KI ENERGY LOCATED?
Well,its located inside all 7 of your chakras.All 7 of your chakras hold different types of energy
HOW DO I MANIFEST KI ENERGY?
All you gotta do is learn how to visualize or use Willpower .
WHERE DO I FIND MORE INFO ON THIS STUFF?
Well my friend.. Google is your friend till the end :D