Modifica el valor de $minimum_amount y pon la cantidad deseada

<?php

add_action( 'woocommerce_check_cart_items', 'required_min_cart_subtotal_amount' );
function required_min_cart_subtotal_amount() {
	
	if ( WC()->cart->get_cart_contents_count() == 0 ) {
        return;
	}

    // HERE Set minimum cart total amount
    $minimum_amount = 10;

    // Total (before taxes and shipping charges)
    $cart_subtotal = WC()->cart->subtotal;

    // Add an error notice is cart total is less than the minimum required
    if( $cart_subtotal < $minimum_amount  ) {
        // Display an error message
        wc_add_notice( '<strong>' . sprintf( __("El importe mínimo para poder hacer el pedido es de %s."), wc_price($minimum_amount) ) . '<strong>', 'error' );
		remove_action( 'woocommerce_proceed_to_checkout', 'woocommerce_button_proceed_to_checkout', 20 );

    }
}