This video explains how to auto-create invoices when an order is ready for it:
One thing to watch for: with Default action set to Create invoice, that invoice goes out already invoiced, which triggers your accounting integration's validation. No active integration on that billing entity, and the validation fails silently — no invoice, no error. If you're not synced to accounting yet, stick with Create draft invoice for now.
‼️ Two settings changed address: Default Invoice date and Default action moved off Organisation settings, Finance and company configuration, onto this same Create invoice task screen. What's left behind is renamed Charge date preference, and only keeps Charge date in dashboards.
Read all about this feature in this article: INVOICES - Auto-create invoice when an order is Ready to invoice.