Yes, FORFEITURE is a Scrabble word!

Letter values in Scrabble US: F 4, O 1, R 1, F 4, E 1, I 1, T 1, U 1, R 1, E 1.

Is it a valid word?

FORFEITURE is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

something that is lost or surrendered as a penalty;
a penalty for a fault or mistake that involves losing or giving up something
the act of losing or surrendering something as a penalty for a mistake or fault or failure to perform etc.