Free or paid community?

Hello, greetings. I'm actually new to all this virtual communities and online courses. Less than a week ago, I launched my first online course and I'm considering creating a community with Fluent Community for my avatar. What I'm not sure about is what's recommended in these cases? Should I make the community free and allow anyone to join and then advertise the courses, or does it generally make more sense to make the community private and only allow people who have already paid for a course to enter? What do you recommend in terms of marketing and what experiences have you had with this topic? I'd like to hear opinions from those who have already done this type of project.