One way to horizontally scale a Django app is to provision additional app servers that run your Django application and its WSGI HTTP server (like Gunicorn or uWSGI). To route and distribute incoming requests across this set of app servers, you can use a load balancer and reverse proxy like Nginx. Nginx can also cache static content and terminate Transport Layer Security (TLS) connections, used to provide HTTPS and secure connections to your app.
The Nginx Ingress Controller consists of a Pod that runs the Nginx web server and watches the Kubernetes Control Plane for new and updated Ingress Resource objects. An Ingress Resource is essentially a list of traffic routing rules for backend Services. For example, an Ingress rule can specify that HTTP traffic arriving at the path /web1 should be directed towards the web1 backend web server. Using Ingress Resources, you can also perform host-based routing: for example, routing requests that hit web1.your_domain.com to the backend Kubernetes Service web1.