@marcolino922 I don’t really know as I don’t speak (or read) Italian. But SCA is needed for most card payments in Europe.
The customer will be prompted to go through the SCA flow on sign-up if necessary. This will create a subscription. There then may be subsequent payments that need SCA authorisation again. You should prompt your customers to approve their payment if this happens. Stripe will send you a webhook notifying you of this, or Cashier will handle sending the notification automatically if you’re using it.