Solomon: A Virtual Learning Environment is open to "guest access". That means that people without a User Id and Password can look at the content of this module. For all the other Modules you need to be an authenticated user.
You are free to enrol on any of the modules, there are no secrets here. However we recommend you do not enrol of modules that are beyond the level you have thus far attained in Freemasonry as it will significantly decrease the impact of your next ceremony or ceremonies. We call them "plot spoilers".