In LifterLMS you can restrict courses to a membership by creating a members only access plan. Members only access plans can be made only available to students active in a membership (or memberships) of your choosing. Please note that members only pricing can be used to create both free and paid access plans.
You have the option to restrict a page or a (blog) post to a membership when creating the page or post. You can do this in the meta box settings at the right side of the screen.
You can use LifterLMS + bbPress to create a members only forum on your website. For more information click here.
Once enabled, bbPress forms can be restricted to one or multiple LifterLMS Memberships.
If you are looking for additional types of content restriction you might need custom development. Check out our LifterLMS Experts if you have questions on custom needs.