Chakra is the foundation on which all life survives on. Consider it the life force of the Ninja World. With it, one is able to perform tasks that would normally be impossible like making giant waves of water to appear out of thin air or creating fire as hot as the sun to burn your enemies. However, it takes a lot of patience and training to increase the quality of one's chakra as well as one's control over it. Chakra is made of two energies present in the human body, physical energy and spiritual energy. When combined together at a given ratio, they can create a technique that is only bound by your creativity and skill.
Physical energy comes from the cells of one's body and when collectively focused, can help increase one's durability and power. It takes extensive training to build up one's stamina that is needed to actually put that energy to good use though. However there are several risky methods to quickly increase one's physical energy like pills or kinjutsu but the drawbacks leave you weakened afterwards if not used correctly or wisely.
As one of the basic five elemental natures, Wind is quite a rarity with only a few known to possess it let alone be a master of it. Wind is quite a wonderful element because of how it interacts with the other basic elements, seemingly appearing to have no weaknesses. When concentrated enough, the wind can be made to be sharp like a sword/knife/razor blade. When applied to weapons like swords, kunai, shuriken, senbon, etc, it can cause piercing/slashing damage that is almost comparable to lightning.