```js

// --- Exercise 1: Array Basics ---

// 1. Create an array with 5 items
const myGames = ["COD", "Minecraft", "Forza", "Clash", "Roblox"];

// 2. Print the entire array
console.log("Entire Array:", myGames);

// 3. Access and print the first element (index 0)
console.log("First Element:", myGames[0]);

// 4. Access and print the last element
// We use .length - 1 because the count starts at 0
console.log("Last Element:", myGames[myGames.length - 1]);

// 5. Print the total number of items
console.log("Total Items in Array:", myGames.length);

// --- Exercise 2: Modify Arrays ---

// 1. Start with the original shopping list
let shoppingList = ["milk", "eggs", "bread", "cheese"];
console.log("Original List:", shoppingList);

// 2. Change the second item to "butter" (index 1)
shoppingList[1] = "butter";

// 3. Add "yogurt" to the end using push()
shoppingList.push("yogurt");

// 4. Remove "bread" (which is at index 2)
// splice(startingIndex, deleteCount)
shoppingList.splice(2, 1);

// 5. Print the final array
console.log("Final Modified List:", shoppingList);

// --- Exercise 3: Loop Through an Array ---

// 1. Create the numbers array
const numbers = [10, 25, 30, 15, 20];
let sum = 0;

console.log("--- Processing Numbers ---");

// 2. Loop through the array
for (let i = 0; i < numbers.length; i++) {
    let currentNum = numbers[i];

    // Print each number with a message
    console.log(`Number: ${currentNum}`);

    // Print each number multiplied by 2
    console.log(`Multiplied by 2: ${currentNum * 2}`);

    // Calculate the sum by adding currentNum to the previous total
    sum += currentNum;
}

// 3. Print the final calculated sum
console.log("--------------------------");
console.log("Total Sum of all numbers:", sum);