Whats the difference between أبیض and بیضا
Well, "أبيض" is masculine, whereas "بيضاء" is feminine. Just don't forget the hamzah (ء) at the end of the latter.
Is hamzah used for every feminine word like ة which is seen many times in case of feminine words?
Why does it tell me I have a typo when it doesn't specify whether it wants a feminine or a masculine color?
Both colours must be of the same sex. So if brown is male, then white must be male as well.