How to change key for array's objects' in javascript?

You can use .map() with Object destructuring:

let data = [
  {Name: "IPHONE8s", Id: 4},
  {Name: "Iphone 9", Id: 5},
  {Name: "IPHONEX", Id: 6}
];

let result = data.map(({Name:text, Id:value}) => ({text, value}));

console.log(result);

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References:

• Array.prototype.map()
• Object destructuring

Example code

function renameKeys(obj, newKeys) {
  const keyValues = Object.keys(obj).map(key => {
    const newKey = newKeys[key] || key;
    return { [newKey]: obj[key] };
  });
  return Object.assign({}, ...keyValues);
}

And use it like:

const obj = { a: "1", b: "2" };
const newKeys = { a: "A", c: "C" };
const renamedObj = renameKeys(obj, newKeys);
console.log(renamedObj)

You could map the objects by mapping the key value pairs with a new name by using an object for the keys and their new name for replacement.

This proposal preserves other properties.

var array = [{ Name: "IPHONE8s", Id: 4, foo: 'bar' }, { Name: "Iphone 9", Id: 5 }, { Name: "IPHONEX", Id: 6 }],
    replace = { Name: 'text', Id: 'value' },
    result = array.map(o => Object.assign(...Object
        .entries(o)
        .map(([k, v]) => ({ [replace[k] || k]: v }))
    ));
    
console.log(result);

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var originalArray = [{Name: "IPHONE8s", Id: 4}, {Name: "Iphone 9", Id: 5}, {Name: 
"IPHONEX", Id: 6} ];
let changeArray = []
for (let i = 0; i < originalArray.length; i++) {
  let tmpObj = {}
  tmpObj.text = originalArray[i].Name
  tmpObj.value = '' + originalArray[i].Id
  changeArray.push(tmpObj) 
}
console.log(changeArray)