Levels of energy are variations in frequency.
Frequencies exist in all things. For example, when your chi, mind, and body are not in sync, one of your chakras is out of whack. That is a specific frequency.
Don't forget, all things begin at the source, another frequency. If you're not in tune with the source, then your frequencies are out. And that includes your thoughts, your consciousness - everything!
Learn to connect using methods, such as yoga, meditation, and all other mindfulness activities. Also, your thoughts create vibrations, that affect everything. More on that later.