Queso chakra is basically your life energy. When you run out, you die. You can use it in a raw form or change it into elements. It goes even further as with things like sealing jutsu as your chakra can make up the actual seal/kanji. Chakra is literally the base of everything in Naruto unless you are Might Guy or Rock Lee. In which they also have chakra, since every living thing has chakra. They just cannot use it like the average shinobi who have been shown to mold their chakra into an element, or several elements. Some even have things such as elemental kekkei genkai, mora, and tota which comes in the form of the combination of several elements or even things like the Sharingan or Byakugan. Chakra can also be used to not only heal others through basically your own life force but it can be used to do things like enhance your strength AKAS akura and Tsunade. It can be used to make strings for puppets, walk on water, it is literally everything in Naruto and the source of a shinobi's power.