Maybe you could approach this in steps. For example, you could start with running a demo flask app in kubernetes like https://github.com/honestbee/flask_app_k8s Then you could look at adding in the database. First you could do this locally like in How can I use MongoDB with Flask? Then to make it work in kubernetes I'd suggest installing the mongodb helm chart (using its instructions at https://github.com/helm/charts/tree/master/stable/mongodb) and then doing kubectl get service to find out what service name and port the deployed mongo is using. Then you can put that service name and port into your app's configuration and the connection should work as it would locally because of kubernetes dns-based discovery (which I see you also have a question about but you don't necessarily need to know all the theory to try it out).