Billie Eilish and Nat Wolff are birds of a feather. The couple made their red carpet debut on Wednesday at the premiere of the singer’s concert film “Billie Eilish – Hit Me Hard and Soft: The Tour (Live in 3D).” Eilish, 24, opted for a bright green Ralph Lauren polo layered over a long-sleeve, white button-down. She paired the look with a black skirt, blue stocking, red socks and white heels. Billie Eilish and Nat Wolff stepped out for their red carpet debut at the premiere of the Grammy winner’s concert film “Billie Eilish – Hit Me Hard and Soft: The Tour (Live in 3D)” on Wednesday (as pictured here). AFP via Getty Images The singer wore a green Ralph Lauren polo, black skirt and heels, while the actor donned a brown suit and dress shoes. Chelsea Lauren/Shutterstock For the occasion, Wolff, 31, donned a brown suit and black dress shoes. While posing for pictures, the “Naked Brothers Band” alum wrapped his arm around the “Ocean Eyes” crooner as he leaned his head on hers.…