During cellular respiration, number of ATP used during conversion of glucose into glyceraldehyde-$3$-phosphate is

Identify the product marked by $\left(\mathrm{i}\right) \& \left(\mathrm{ii}\right)$ in the following pathway

Which enzyme is required for the following conversion?

$\mathrm{Pyruvic} \mathrm{acid} + \mathrm{CoA} + {\mathrm{NAD}}^{+}⟶\mathrm{Acetyl} \mathrm{CoA}+{\mathrm{CO}}_2+\mathrm{NADH}+{\mathrm{H}}^{+}$