notation question
For custom positions usually you'd like to use FEN as it stores all required info, e.g.:
rnbqk1nr/pppp1ppp/8/8/2B1P2b/5N2/PPPP3p/RNBQ1R1K b kq - 1 7
You can read all about it in the article below:
https://www.chess.com/terms/fen-chess