Add learners to a course

Hello,

I am hosting a course for a client using his Squarespace, and I cannot figure out how to add learners to a course and help then navigate back to the course on return visits.

They are paying via invoice, so I don't need a digital product purchase flow at all.

There's no courses topic tag available, so I have no idea what the visibility on this will be like in Forums. 

Thanks!  

If you create a course and add a paywall to it, then learners will go to the course page, pay for access, and get it added to their account. If you add the login/account option to your navbar, users can then log in and see a link to all courses they have paid for. As far as I know, there is not a way to pay for courses via invoice (as of posting this), but such a feature would be helpful.