Explain: Where are $ATP$ and $NADPH$ used?

(N/A) $ATP$ and $NADPH$ are the primary products of the light-dependent reactions of photosynthesis. They are utilized in the biosynthetic phase (also known as the dark reaction or Calvin cycle) to drive the synthesis of sugars from $CO_{2}$ and $H_{2}O$.
$1$. Biosynthetic Phase: This phase does not directly require light but depends on the $ATP$ and $NADPH$ produced during the light reaction. These molecules provide the necessary energy and reducing power to convert $CO_{2}$ into carbohydrates.
$2$. Calvin Cycle ($C_{3}$ Pathway): In this pathway,$CO_{2}$ is fixed into a $3$-carbon compound called $3$-phosphoglyceric acid $(PGA)$. $ATP$ and $NADPH$ are consumed to reduce $PGA$ into triose phosphates,which are eventually converted into glucose.
$3$. $C_{4}$ Pathway: In plants following the $C_{4}$ pathway,$CO_{2}$ is initially fixed into a $4$-carbon acid called oxaloacetic acid $(OAA)$. $ATP$ is specifically required to regenerate the $CO_{2}$ acceptor molecule $(PEP)$ in these plants,in addition to the requirements of the Calvin cycle.