The site should be running already on the server - webtech-03.napier.ac.uk

If it's not (or it breaks to the extent it needs a restart), then run the command gunicorn3 --worker-class eventlet -w 1 main:app --bind 127.0.0.1:8000 from the site's directory. If that's still not working, restart nginx, which passes through the traffic.

Be sure to kill the old process first, which is running in the background using nohup ... & and can be viewed by running jobs.

Local deployment is a bit of an involved process, as sockets are used. For a limited functionality (which may break due to lack of socket support), then python3 main.py can be used.

For a more complete deployment, install gunicorn3 (via apt) and eventlet (via pip3), and then run the command above.