Hello there, hope you are doing good!
I would like to tell you that an open course is when a student undertakes an education course only from distance education through a college or university that provides an open degree. Open degree courses are different from regular degree courses, open degree courses can be customised according to the student's choice like a Bachelors of Arts (BA) in different subjects and more. An open course have less requirements for a student to pursue, or take admission in than a full time regular degree.
Hope you found this answer helpful.
Good luck for your future!