Is the prayer of one who performs the pillars and duties of prayer valid, even if he does not differentiate between a pillar and a duty?

It is not a condition for the validity of prayer that the worshiper memorizes its pillars and obligations, if he performs them as required. So, if the worshiper learns the manner of prayer from a scholar, his prayer is valid as long as it is free from defects, even if he does not distinguish between obligations and non-obligations, or believes all of them are obligatory, or believes all of them are Sunnah, or believes that an obligation is Sunnah or vice versa, or that it is a virtue, or believes that every part of it is an obligation.

This is confirmed by the Prophet's saying: "Pray as you have seen me praying," for he only commanded them to do what they had seen, and religious scholars are like the Prophet in being worthy of emulation.