Class room session- scheduled instance?

Hi All,

I have created a classroom session for a course provided by an external vendor. I'd like the course to be visible in the catalogue to allow learners to enrol to it, and based on the interest to schedule a session.

Can anyone provide advice on what would be the correct setup? can I use the default instance for the first scheduled session or do I need to create a separate instance for that?

Thanks

Roni