How can I turn my pawn into a queen?
One of the more surprising rules of chess, when you see it for the first time, is Pawn Promotion. This rule means that if you can get one of your pawns all the way to the other end of the board, you can turn it into any piece you want! (other than a king!)
White is about to promote their pawn! On white's turn, when they move the pawn forward to the 8th rank, the opposite side of the board, they will get an option to choose their new piece:
White gets to choose a queen, knight, rook or bishop to replace their pawn!
Due to this rule, you can sometimes see two, or even more, queens of the same color on the board!
In almost all cases it is best to promote to a queen, though in some very rare cases it may be better to promote to a knight, in order to check a king immediately where a queen couldn't, for example.
Take a look at this game, where Chessbrah GM Aman Hambleton wins with six queens on the board!