Oracle JET components are designed to generate content that conforms to the WCAG 2.0 AA standards. In most cases, you don't need to do anything to add accessibility to the Oracle JET component. However, there are some components where you may need to supply a label or other property.
For those components, the component's API documentation contains an Accessibility section that provides the information you need to ensure the component's accessibility.
Some Oracle products have run-time accessibility modes that render content optimized for certain types of users, such as users of screen readers. For the most part, Oracle JET renders all accessibility-related content all of the time. There is only a mode for users that rely on the operating system's high contrast mode, which is described in Creating Accessible Oracle JET Pages.
Oracle JET components that provide keyboard and touch navigation list the keystroke and gesture end user information in their API documentation. Since the navigation is built into the component, you do not need to do anything to configure it.