I have a pond at home with a new pet koi named spot
Koi is actually an informal group of the Amur carp. It's a colored variant.
oh ok, since I am a novice in Koi fish, I always thought they were like goldfish
That's understandable, but Koi varieties are distinguished by their colors and patterns.
mine is orange and white, is that a common color?
They were originally eaten as a food dish, but they have varied colors. Those are common colors that I have seen before.