With Electa Live you can create paid online courses and paid online classes. Students can enroll to paid course (or subscribe to attend paid live classes) only upon submitting a payment. For each paid item you can specify the enrollment/subscription price and currency.
To accept payments from students you need to have at least one active payment profile configured on your account. Payment Profiles are actually where the payments from your students go. How to configure my Electa Live account to accept payments from students.
So everyone who wants to attend such a paid event or enroll in a paid course must first submit a payment and then he will be given individual access. Students cannot exchange links because the authentication is for each individual student and only one person can join with a specific username/password.
The following guide explains how to schedule paid online course. You may also have a look at the article explaining how students enroll in paid courses.