Hi,
To integrate Moodle and WordPress, you can use the Edwiser Bridge plugin. This plugin allows you to import Moodle courses to your WordPress site.
To sell your Moodle courses in WordPress, you can use the Edwiser Bridge WooCommerce integration plugin which is a premium extension of Edwiser Bridge.
To enable SSO between both system, you can integrate the Single Sign On plugin that allows your user to simultaneously login to both systems.