You can access JMP tutorials by selecting Help > Tutorials. The first item on the Tutorials menu is Tutorials Directory. This opens a new window with all the tutorials grouped by category.
If you are not familiar with JMP, start with the Beginners Tutorial. It steps you through the JMP interface and explains the basics of using JMP.
The rest of the tutorials help you with specific aspects of JMP, such as designing an experiment and comparing a sample mean to a constant.