Some of these may require you to register but should be absolutely free without a “trail free period” with the of a credit card.

https://www.coursera.org/learn/intro-to-artificial-intelligence
https://www.coursera.org/learn/fundamentals-of-machine-learning-and-artificial-intelligence
https://www.coursera.org/learn/exploring-artificial-intelligence-use-cases-and-applications
https://www.coursera.org/learn/ai-security
https://www.coursera.org/learn/responsible-artificial-intelligence-practices

https://www.coursera.org/learn/exploring-artificial-intelligence-use-cases-and-applications

https://ocw.mit.edu/courses/6-034-artificial-intelligence-fall-2010/resources/lecture-videos/

Partial courses
Coursera introduction to ai (Google) full course but you have to decline trail https://www.coursera.org/learn/google-introduction-to-ai/home/module/1
Coursera ai-for-everyone (only week 1) https://www.coursera.org/learn/ai-for-everyone
Coursera introduction to ai (OBM) (only module 1) https://www.coursera.org/learn/introduction-to-ai/home/module/1

Incomplete free Book from Berley Course on AI
https://aima.eecs.berkeley.edu/4th-ed/pdfs/