Where does the promoting piece begin?

Answer 1

Since the only piece that may be promoted is a pawn, a "promoting piece" begins on the second rank for White and on the seventh rank for Black. The numbering of the two ranks is done in accordance with standard algebraic Chess notation.

I think the person asking the question means that he/she want to know where the promoted piece is placed to begin its moving. If this is what the questioner meant by their question then the answer is this:As the original answer person stated, only a pawn can be promoted. For a White pawn to be promoted the White pawn must advance onto the last rank on the Black side which is numbered as rank #8. For a Black pawn to be promoted the Black pawn must advance onto the last rank on the White side which is numbered as rank #1.For which ever color pawn to get promoted, at the point where the pawn reaches the last rank of its opponent, the pawn to be promoted may promote to either a Queen, Rook, Bishop or Knight. The promoted piece is then placed on the same exact RANK AND FILE that the pawn reached on his opponents last rank to begin its move.