Hello @AngelaRhone ...
Please review How do I add users to a course?. In particular, be sure to read the information in the light blue box at the top of that page...as your school may already have systems in place to add people to courses automatically via SIS (Student Information System) import. You'd want to consult with your school's Online Learning / eLearning / Distance Learning department on the specifics, though.
Hope this helps!
