How do I give a player a chess piece in a crazyhouse study?

I am trying to make a study and when I make the chapter (it is crazyhouse) but how do I give one player a piece in the inventory on the side?

Oops, grammar error, sorry! ',' not 'but'!

Use an extension of FEN where the pieces are listed at the end of the first field.

Example:
rnbqkb1r/ppp1pppp/8/3n4/3P4/8/PPP2PPP/RNBQKBNR/Pp w KQkq - 0 4

White has a pawn (P) and Black has a pawn(p).