The second stage of photosynthesis uses energy from the first stage to make sugars. The second stage is referred to as the light-independent reactions. These reactions occur in the stroma and use CO2 molecules. 

A molecule of glucose is formed as it stores fome of the energy captured from sunlight. During the Calvin Cycle, energy is added and carbon molecules are rearranged. A high-energy 3-carbon molecule leaves the cycle. 

Two 3-carbon molecules bond to form a sugar. The remaining molecules stay in the cycle. 

Here are some resources you need to take the time to check out regarding the Calvin Cycle: