You can search online, consult friends and classmates, or directly contact the training institution to purchase.

1. Online search: Use a search engine or education and training website to search for "Peanut 13 Public Examination Course" to learn more about the course and how to purchase it.

2. Consult friends or classmates: If you know people who have participated in similar courses, you can ask for purchasing experience and recommendations.

3. Contact the training institution directly: If you already know the training institution that provides the course, you can contact it directly to learn about the purchase method and course schedule.