Add a new app to an existing project

Run this command:

python manage.py startapp app_new_app_name

settings.py - add your app to the installed apps (the name will be the same as the class name found in apps.py):

INSTALLED_APPS = [
  ...
  'app_new_app_name.apps.NewAppNameConfig',
  ...
  ]

urls.py - project level:

All pages for this app will have this url: new_app/

urlpatterns = [
  ...
  path("new_app/", include("app_new_app_name.urls")),
  ...
]

urls.py - app level:

from django.urls import path
from app_new_app_name.views import *

urlpatterns = [
    # create a view and add a new path
]

Create folders in the app directory:

app_new_app_name
    templates
        app_new_app_name