No. Amazon does not offer free physical books. However, Kindle Unlimited sometimes includes Kannada health books for a 30-day free trial.

Join a Kannada literature WhatsApp or Telegram group (strictly for educational purposes). Ask members if they have a scanned copy of the ₹20 edition. Many group admins share old, out-of-print books for free because no publisher is currently selling them.

Use Google Books preview. Search for "Rathi Vignana" and filter by "Preview available." You may not get the full book, but you will get the first 20 pages for free—legally.