How to correctly stop gunicorn from running?

Question

Flask

Greetings.
Installed gunicorn. Launched gunicorn. Close VSCode. The site works locally at 127.0.0.1:8000 . Hmm...
Tried to make changes to the application code. The changes did not appear on the site. In some way, I dug something like this on the network: "find some ports, shut them down." I did that, but now gunicorn won't start. Rebooted the computer, earned gunicorn.
Tell us how to work with gunicorn. How to terminate the process? How to make it so that when you change the code in the application, the changes appear on the site?