How can I do to setup the amount to $0 without having multi-level or set donatio

HI there,

Currently, Give requires a minimum donation amount of at least $1. If that isn’t present then you’ll see an alert about the minimum donation. But, one workaround is that you can focus the cursor on the custom amount field on page load which effectively clears out that field completely. This snippet will do that for you:

function my_give_focus_custom_amount() { ?>
    <script>
        jQuery("#give-amount").focus();
    </script>

<?php }
add_action( 'give_payment_mode_top', 'my_give_focus_custom_amount' );

If you need guidance implementing custom PHP functions on your website, we have this guide here: https://givewp.com/documentation/resources/adding-custom-functions-to-your-wordpress-website/

Thanks!