map_users.js

const users = [
  {
    id: 1, 
    name: "Allan", 
    age: 27, 
    profilePicture: "http://…", 
    city: "São Paulo"
  },
  {
    id: 2, 
    name: "Julie", 
    age: 29, 
    profilePicture: "http://…", 
    city: "Curitiba"
  },
  {
    id: 3, 
    name: "Pedro", 
    age: 31, 
    profilePicture: "http://…", 
    city: "Rio de Janeiro"
  }
]

const names = users.map(user => user.name)

console.log(names)
// ["Allan","Julie","Pedro"]