• Download and install the Google Chrome browser if you don't already have it installed
• Open the dev tools with F12 or by following the picture below

• For better control open the dev tools in a separate window

• Then you can fullscreen it and navigate to the sources menu

• Then go to snippets

• Click "New snippet" and name it whatever you wish. I'll name it "Hello Javascript"

• Type in the following code:

function basicFunction(first, second, border, link) {    
    return border + first + link + second + border;
}

let var1 = 'Hello'
let var2 = 'Javascript'
let sides = '!!'
let between = ' '

let result = basicFunction(first=var1, second=var2, border=sides, link=between);

console.log(result)

Click the run icon/button

Notice the output in the console

!!Hello Javascript!!