Implement a generic RequiredByKeys<T, K> which takes two type argument T and K.

required-by-keys.ts

interface User {
  name?: string
  age?: number
  address?: string
}

type RequiredByKeys<T, K = keyof T> = Merge<
  {
    [P in keyof T as P extends K ? P : never]-?: T[P]
  } & {
    [P in keyof T as P extends K ? never : P]: T[P]
  }
>

type Merge<T> = {
  [P in keyof T]: T[P]
}

type UserRequiredName = RequiredByKeys<User, 'name'> 
// { name: string; age?: number; address?: string }