Where do plants get the gas needed for this process

Plants must get food into their systems in order to acquire energy and continue living, similar to animals. Plants create energy for animals to use, so they must replenish their nutrients. And plants breathe, in a way. They take in the carbon dioxide that all the animals give off, and they give off oxygen for all the animals to use. Photosynthesis is the process by which plants convert energy from the sun. It is the process that allows plants to create organic molecules that they use as fuel. Hope this helped!