it must be a diagram as mentioned above

Here is an example of what the Dialog Map for the "Student submits assignment" use case might look like:

Student opens the EDUGATE website and clicks the "Sign In" button.

Student enters their login credentials and clicks the "Sign in" button.

The system checks the student's credentials and logs them in.

Student clicks on the "Dashboard" tab to navigate to the courses page.

Student selects their course and assignment from the dashboard menu.

Student clicks on the assignment to select their submission file.

Student clicks the "Submit" button to submit their assignment.

The system confirms that the assignment has been successfully submitted

Create a Dialog Map using Visual Paradigm for the use case: "Student submits assignment" through the edugate system. Follow the process on the edugate website and model the user interface elements and triggers