How do I make an alert? [duplicate]

You can do it the traditional way via javascript. However the options are set to ok or cancel, since confirm is implemented internally in each browser.

<script>
    confirma() {
        if (confirm('Deseja realmente fazer determinada ação?')) {
            // código caso tenha confirmado
        } else {
            // código caso tenha cancelado
        }
    }
</script>

<button onClick="cofirma();"> Botão de confirmação <button>

If it does not suit what you want, since it is something much more specific, I recommend looking for a solution via a plugin, such as Bootstrap modals.

You can use the confirm function that is native to browsers. It returns true or false according to the user response.

if (confirm('Deseja ir para a página de configurações?')) {
    window.location.href = 'config.php';
}

It's possible, yes, you can do it this way:

if (confirm('Deseja mudar de pagina?')) {
     window.location.href='http://google.com';
} else {
    // fica na pagina
}

You can use javascript, you can look at this link , and in that here is an example