First, it’s worth considering what energy actually is.
Rather than being an actual “thing” in the universe, energy is best thought of as an abstract (there’s no such thing as pure energy).
The useful thing about energy, and the only reason anyone ever even bothered to name it, is that energy is conserved.
If you sum up all of the various kinds of energy one moment, then if you check back sometime later you’ll find that you’ll get the same sum.
Energy takes a heck of a lot of forms: kinetic, chemical, electrical, heat, mechanical, light, sound, nuclear, etc. For example, the energy stored in a (not overly) stretched or compressed spring is and the energy of the heat in an object is .