JSFiddle - React, Tailwind, and code Playground

JavaScript

// Array Of Cities
var countries = [
    {
        "country": "Indonesia",
        "city": "Jakarta",
        "population": 30539
    },
    {
        "country": "India",
        "city": "Delhi",
        "population": 24998
    },
    {
        "country": "Philippines",
        "city": "Manila",
        "population": 24123
    },
    {
        "country": "Japan",
        "city": "Tokyo",
        "population": 37843
    },
    {
        "country": "The Republic of Korea",
        "city": "Seoul",
        "population": 23480
    },
    {
        "country": "China",
        "city": "Shanghai",
        "population": 23416
    },
    {
        "country": "Pakistan",
        "city": "Karachi",
        "population": 22123
    },
    {
        "country": "China",
        "city": "Beijing",
        "population": 21009
    },
    {
        "country": "USA",
        "city": "New York City",
        "population": 20630
    },
    {
        "country": "China",
        "city": "Guangzhou",
        "population": 20597
    }
];

// Input N number
var numberOfCity = +prompt("Enter the number of cities to print in console");

// Check input to number
function isNumeric(n) {
    return !isNaN(parseFloat(n)) && isFinite(n);
}

// Sort by population
function sortCitiesPopulation(a, b) {
    if (a.population > b.population) return -1;
    if (a.population < b.population) return 1;
}

// Print N cities in console
function printList(numberOfCity, arrayToPrint) {
    for (var i = 0; i < numberOfCity; i++) {
        console.log("Country: " + arrayToPrint[i].country + " City: " + arrayToPrint[i].city + " Population: " + arrayToPrint[i].population);
    }
}

if (isNumeric(numberOfCity) && numberOfCity > 0) {
    countries.sort(sortCitiesPopulation);
    printList(numberOfCity, countries);
} else {
    alert("You must enter number > 0!");
}