Your Brightspace courses are listed in two places -- the My Courses widget on the organizational homepage and the Course Selector waffle icon, which will follow you throughout Brightspace.
To access a course, select the course. If the course is not yet available, it should give some indication of when it will begin or end underneath the course name in the My Course widget.
A few reasons this may happen:
How do I know whether I have waitlisted or full student access to a Brightspace course?
After the course ends:
Find your courses and more from the organizational homepage in Brightspace