To add new arenas to the database Arena table, a view function for processing and a Jinja2 HTML template will be created and used. The function will determine the request method and will send the appropriate response to the request. If it is a GET request, it will send an HTML template with the AddForm form. From the HTML template, filling in the data and pushing the button will submit a POST request, which will go to the same view function, and will use the submitted data to add a new row to the Arena table.