Only group authenticated participant

Hi all

Here is the situation,

I have a Pro plan account, I have multiple classes of students, The classes have different times, firstly I add students as users to send an invitation to my account, then I create groups and add every student to his group,

Problem 1,

I want to schedule a meeting for every group, how do I create a scheduled meeting for each group exclusively,

Problem 2,

I want only authenticated participants to join the meeting and no one else can join even if he has the invitation link,

Thanks in advance