How should I go about building an admin dashboard for my software engineering portfolio?

Question

I'm looking to improve my portfolio by building a full-stack admin dashboard app for a courier business.

The app would feature two versions—admin and driver—and would include the following:

driver

• click-in/clock-out
• pause/rest
• live ticking clock to display hours worked
• money earned based on rate set by admin
• etc.

admin

• dashboard showing live clock of total time worked by driver(s)
• live money clock showing amount owed to driver(s)
• live money clock showing approximate gross income based on hours driven
• payroll reports
• rates for driver
• etc.

My questions:

1. Since this is not for an actual business, and will not be used by one, how do I showcase it on my portfolio? Do I create a screen-recording of me navigating the app while logged in as an admin/driver, or would I create a separate demo module to allow people to see my work?

2. How would the backend work for this? What data would I use in my demo?

3. I'm using MySQL, would I deploy the app and pay for a domain and database even though nobody would be using it?

Thank you in advance.