Main Settings / General Settings / Higher Education Customization / Basic Settings / Check for existing Group limits in Group enrollments
Here you define whether there will be a limit check when students are enrolled in groups.
Note: You must have the “Enable Configuration for Higher Education” setting enabled.
Example
Setting -> Warning
When you select a group and the limit of registered students has been exceeded you will receive the following warning
Note: To set a limit on a group go to the group and set a number as shown below