With LifterLMS Private Areas you have the option to sell a course or a course + coaching package for different prices.
To do this you will want to create two different access plans. Check out our related documentation for more information on Access Plans.
As you start selling your course + coaching you can when you get sales of the access plan that includes the coaching you can start creating private posts for that customer with Private Areas.
If you want to begin a series of private posts that drip out over time you can trigger this via automations.