How much will it cost to repair a key from the keyboard? If the nipple is broken?
I tried using crazy glue and I just made it worse
Hi,
Bring the Mac to an Apple Store “genius” bar: https://support.apple.com/contact I've heard from people here that employees have actually replaced a key or mechanism for free when they happened to have one laying around. I wouldn't count on that, but I'd certainly go to find out if a store was convenient.
Otherwise, you can buy them at a place like this Apple MacBook Pro Laptop Key Replacement (Retina Display) - ReplacementLaptopKeys.com or on eBay and replace them yourself if you can figure out how.