Is it permissible to say that the two rak'ahs of Duha, which suffice as charity for every joint in the human body (360 joints), can be counted as 360 charities, multiplied tenfold to become 3600, then multiplied by a thousand (in imitation of those who say that prayer in the Prophet's Mosque is equivalent to a thousand prayers) to become three million and 600 thousand charities, or is this from the matters of the unseen?

This matter is from the Unseen, known only to Allah. It is about the multiplication of good deeds, which is based on Allah's acceptance of them. Therefore, a Muslim should not preoccupy himself with this, but rather with performing deeds, doing so with sincerity and perfection, and ensuring they align with the requirements of Islamic law. The Duha prayer suffices for charity for every joint in the body and takes its place, which indicates its immense virtue.