How to setup Access Levels and Subscription Plans


I'm trying to create a tutorial website and need some help with the creation of access levels, subscription plans, ...

Visitors should get access to some free tutorials and only to be able to become free members.

Free members get access to some basic tutorials. The free membership should be indefinite

Free members should be able to upgrade to a premium membership for a fixed prices each month and with access to some premium content that is "dripped" every month and this for an idefinite time (if possible).

If premium members do not pay the membershipfee they should become free members again.

If anyone can help with this I would really appreciate it.