Student wants to enroll a Course. Form validation, Entity validation, etc.

If the student in this overview is already authenticated wouldn't it make more sense to check if they have the required points before displaying the enrolment form?

if($student->points() > $course->min_points)
{
    return view('course.enrole', compact('student', 'course');
}

//Set notification that they do not have the minimum points etc.
return redirect()->route('home');

You could even disable the hyperlinks point to the enrolment pages based on minimum points using some sort of presenter. Besides points, if there are a number of criteria that would prevent or allow a student to enrol I would rather check those before and then, once the form is submitted, check them again using an "Enrolement" class that would validation non-form driven values, e.g. minimum points etc.

use Middleware.

use Model and Middleware for that