The Nimzo is indeed an opening for black.
Chess Personality - “The Professional”

What I don’t understand is the recommendation for the Nimzo-Indian as an opening for white? I thought it was the Nimzo-Indian “defense” that you can play as black against white’s d4 opening. Can someone explain this? Thanks!
A defense is also an opening, but then when playing as black instead of white
What I don’t understand is the recommendation for the Nimzo-Indian as an opening for white? I thought it was the Nimzo-Indian “defense” that you can play as black against white’s d4 opening. Can someone explain this? Thanks!