Screen sharing from PC / Laptop

How the student can share his screen from PC / Laptop during the live class. Unable to find any option from the available menus.

Teacher has to give “Presenter Access” to the students to enable screensharing for a student.

For teachers on Laptop/PC → Go to people, click on student and select make presenter to give screen sharing access

For teachers using mobile app / TeachmintX device → Click on share screen icon, give sharing access

Thanks for the detailed explanation.
Once the teacher granted access for the student attending from PC / Laptop, which tab / icon to be used to share the screen. Is there any button similar to the one in mobile app is available to share the screen from Web.

Once student has the presenter access, they can see the button to start sharing screen