Which Shirt And Tie To Wear With Party Grey Suit Matching Clothes Boyfriend & Me?

Matching clothes boyfriend & me? - which shirt and tie to wear with party grey suit

Hey,
Me and my friend goes to a mere formality.
I have a red dress, the better in a gray suit?
His gray suit, white shirt with thin blue stripes and dark burgundy red. What color tie he should wear?
Thank you!