Kundalini Shakti is your life-force energy/spirit/innate intelligence, and when it is awakened a whole to level of consciousness develops - clarity, happiness and peace. There are different approaches to awakening kundalini shakti, and it’s best to receive instruction from a qualified yogi from an established lineage.
Sai is trained in several lineages and is using the shaktipat transmissions on the 3rd Eye and Crown Chakra as taught to him by the the great Siddha Vethathiri Maharishi from the Tamil Nadu state of India. .
Here is a video of instruction being given to students in Rishikesh, India, at the Maa Yoga Ashram, January 2018.