How do I change language

Hello, I would like to find a way to change my website’s language based on the cookie that I have made it save.
I have a custom plugin that saves the language cookies like this:

function aws_set_language_cookie() {

    //To save the language in a cookie
    
    $current_language = get_locale();
    
    if ($current_language == "es_ES") {
        $result = setcookie('lang', $current_language, time() + (30 * DAY_IN_SECONDS), '/');

    } else {
        $result = setcookie('lang', $current_language, time() + (30 * DAY_IN_SECONDS), '/');
    }

    //To read the cookie and change the language based on the cookie
    
    if (isset($_COOKIE['lang']) && $_COOKIE['lang'] == "es_ES") {
        //need code to change website language to spanish here
    }
}

How do I change the language to Spanish inside the last if statement?

The plugin I use to change my website’s language is called TranslatePress

The page I need help with: [log in to see the link]