Plant cells use their chloroplasts via the Calvin cycle to store the suns energy in the form of ATP, and more complex forms such as glucose and fructose. They form the these sugars by the basic reaction process
6CO2 + 12H2O + light -> C6H12O6 + 6O2 + 6H2O
carbon dioxide+water+ light->glucose+ oxygen+water
I could explain the reaction, but that includes typing a bunch of RuBisCOs, 3-phosphoglycerate, 3-phosphoglyceric acid, and other complex enzyme names that take a long time to type and I have no idea what they mean. hope that helped