Need help in installing Flask

Hello there,

Pls help in installation of flask. while running the command "python -m flask run", I am getting this error placed below.

Pls find enclosed the screenshot of my visual code as well for more clarity of my issue. I have installed flask as per the directions given in the flask tutorial in Visual studio code(attached its screenshot also).

PS C:\Users\Aarushi Kumar\Desktop\hello_flask> python -m flask run
Usage: python -m flask run [OPTIONS]
Try 'python -m flask run --help' for help.

Error: Could not locate a Flask application. Use the 'flask --app' option, 'FLASK_APP' environment variable, or a 'wsgi.py' or 'app.py' file in the current directory.
PS C:\Users\Aarushi Kumar\Desktop\hello_flask>

thanks