In order to post to the forum you need an account in moodle and self-enroll in this course. Creating an account is easy and so is self-enrolling.
To create a user go here and complete your details, including the confirmation email. To self-enroll in the "OSCAR/Surface Resource Portal", go here and click on "self-enroll" and confirm at the bottom of the following the new screen.
You can then post to this forum and access the other materials.