For a deeper understanding of ISO 9001:2015, you can follow this learning path:

1. Use the Guided learning feature from Experta.
2. Take the free online training ISO 9001 Foundations Course: https://advisera.com/training/iso-9001-foundations-course/ to learn about the basics of the standard.
3. Read the standard itself.
4. Read more in-depth articles about ISO 9001: https://advisera.com/iso-9001/.

Additionally, you can enroll in the ISO 9001:2015 Lead Implementer Course and ISO 9001:2015 Lead Auditor Training Course for free to gain more specialized knowledge.